82 changed files with 1936 additions and 2869 deletions
--- a/.envrc
+++ b/.envrc
@ -1 +0,0 @@
-use flake
--- a/.gitignore
+++ b/.gitignore
@ -3,4 +3,3 @@
 /pki
 **/*.rs.bk
 *.swp
-/.direnv
--- a/Cargo.lock
+++ b/Cargo.lock
@ -1048,7 +1048,7 @@ dependencies = [

 [[package]]
 name = "garage"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "assert-json-diff",
 "async-trait",
@ -1080,6 +1080,7 @@ dependencies = [
 "parse_duration",
 "prometheus",
 "rand 0.8.5",
+ "rmp-serde",
 "serde",
 "serde_bytes",
 "serde_json",
@ -1095,7 +1096,7 @@ dependencies = [

 [[package]]
 name = "garage_api"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "async-trait",
 "base64",
@ -1140,7 +1141,7 @@ dependencies = [

 [[package]]
 name = "garage_block"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "arc-swap",
 "async-compression",
@ -1155,6 +1156,7 @@ dependencies = [
 "hex",
 "opentelemetry",
 "rand 0.8.5",
+ "rmp-serde",
 "serde",
 "serde_bytes",
 "tokio",
@ -1165,7 +1167,7 @@ dependencies = [

 [[package]]
 name = "garage_db"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "clap 3.1.18",
 "err-derive",
@ -1180,7 +1182,7 @@ dependencies = [

 [[package]]
 name = "garage_model"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "arc-swap",
 "async-trait",
@ -1198,6 +1200,7 @@ dependencies = [
 "netapp",
 "opentelemetry",
 "rand 0.8.5",
+ "rmp-serde",
 "serde",
 "serde_bytes",
 "tokio",
@ -1207,7 +1210,7 @@ dependencies = [

 [[package]]
 name = "garage_rpc"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "arc-swap",
 "async-trait",
@ -1226,6 +1229,7 @@ dependencies = [
 "pnet_datalink",
 "rand 0.8.5",
 "reqwest",
+ "rmp-serde",
 "schemars",
 "serde",
 "serde_bytes",
@ -1237,9 +1241,8 @@ dependencies = [

 [[package]]
 name = "garage_table"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
- "arc-swap",
 "async-trait",
 "bytes",
 "futures",
@ -1251,6 +1254,7 @@ dependencies = [
 "hexdump",
 "opentelemetry",
 "rand 0.8.5",
+ "rmp-serde",
 "serde",
 "serde_bytes",
 "tokio",
@ -1259,7 +1263,7 @@ dependencies = [

 [[package]]
 name = "garage_util"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "arc-swap",
 "async-trait",
@ -1272,11 +1276,9 @@ dependencies = [
 "garage_db",
 "git-version",
 "hex",
- "hexdump",
 "http",
 "hyper",
 "lazy_static",
- "mktemp",
 "netapp",
 "opentelemetry",
 "rand 0.8.5",
@ -1292,7 +1294,7 @@ dependencies = [

 [[package]]
 name = "garage_web"
-version = "0.8.1"
+version = "0.8.0"
 dependencies = [
 "err-derive",
 "futures",
--- a/Cargo.nix
+++ b/Cargo.nix
@ -32,7 +32,7 @@ args@{
  ignoreLockHash,
 }:
 let
-  nixifiedLockHash = "8461dcfb984a8d042fecb5745d5da17912135dbf2a8ef7e6c3ae8e64c03d9744";
+  nixifiedLockHash = "90b29705f5037c7e1b33f4650841f1266f2e86fa03d5d0c87ad80be7619985c7";
  workspaceSrc = if args.workspaceSrc == null then ./. else args.workspaceSrc;
  currentLockHash = builtins.hashFile "sha256" (workspaceSrc + /Cargo.lock);
  lockHashIgnored = if ignoreLockHash
@ -56,15 +56,15 @@ in
 {
  cargo2nixVersion = "0.11.0";
  workspace = {
-    garage_db = rustPackages.unknown.garage_db."0.8.1";
-    garage_util = rustPackages.unknown.garage_util."0.8.1";
-    garage_rpc = rustPackages.unknown.garage_rpc."0.8.1";
-    garage_table = rustPackages.unknown.garage_table."0.8.1";
-    garage_block = rustPackages.unknown.garage_block."0.8.1";
-    garage_model = rustPackages.unknown.garage_model."0.8.1";
-    garage_api = rustPackages.unknown.garage_api."0.8.1";
-    garage_web = rustPackages.unknown.garage_web."0.8.1";
-    garage = rustPackages.unknown.garage."0.8.1";
+    garage_db = rustPackages.unknown.garage_db."0.8.0";
+    garage_util = rustPackages.unknown.garage_util."0.8.0";
+    garage_rpc = rustPackages.unknown.garage_rpc."0.8.0";
+    garage_table = rustPackages.unknown.garage_table."0.8.0";
+    garage_block = rustPackages.unknown.garage_block."0.8.0";
+    garage_model = rustPackages.unknown.garage_model."0.8.0";
+    garage_api = rustPackages.unknown.garage_api."0.8.0";
+    garage_web = rustPackages.unknown.garage_web."0.8.0";
+    garage = rustPackages.unknown.garage."0.8.0";
    k2v-client = rustPackages.unknown.k2v-client."0.0.1";
  };
  "registry+https://github.com/rust-lang/crates.io-index".addr2line."0.17.0" = overridableMkRustCrate (profileName: rec {
@ -1494,16 +1494,16 @@ in
    };
  });
  
-  "unknown".garage."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/garage");
    features = builtins.concatLists [
      (lib.optional (rootFeatures' ? "garage/bundled-libs" || rootFeatures' ? "garage/default") "bundled-libs")
      (lib.optional (rootFeatures' ? "garage/consul-discovery") "consul-discovery")
      (lib.optional (rootFeatures' ? "garage/default") "default")
-      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/k2v") "k2v")
+      (lib.optional (rootFeatures' ? "garage/k2v") "k2v")
      (lib.optional (rootFeatures' ? "garage/kubernetes-discovery") "kubernetes-discovery")
      (lib.optional (rootFeatures' ? "garage/lmdb") "lmdb")
      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/metrics") "metrics")
@ -1522,14 +1522,14 @@ in
      bytesize = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".bytesize."1.1.0" { inherit profileName; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_api = (rustPackages."unknown".garage_api."0.8.1" { inherit profileName; }).out;
-      garage_block = (rustPackages."unknown".garage_block."0.8.1" { inherit profileName; }).out;
-      garage_db = (rustPackages."unknown".garage_db."0.8.1" { inherit profileName; }).out;
-      garage_model = (rustPackages."unknown".garage_model."0.8.1" { inherit profileName; }).out;
-      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.1" { inherit profileName; }).out;
-      garage_table = (rustPackages."unknown".garage_table."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
-      garage_web = (rustPackages."unknown".garage_web."0.8.1" { inherit profileName; }).out;
+      garage_api = (rustPackages."unknown".garage_api."0.8.0" { inherit profileName; }).out;
+      garage_block = (rustPackages."unknown".garage_block."0.8.0" { inherit profileName; }).out;
+      garage_db = (rustPackages."unknown".garage_db."0.8.0" { inherit profileName; }).out;
+      garage_model = (rustPackages."unknown".garage_model."0.8.0" { inherit profileName; }).out;
+      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.0" { inherit profileName; }).out;
+      garage_table = (rustPackages."unknown".garage_table."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
+      garage_web = (rustPackages."unknown".garage_web."0.8.0" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      sodiumoxide = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".kuska-sodiumoxide."0.2.5-0" { inherit profileName; }).out;
      netapp = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".netapp."0.5.2" { inherit profileName; }).out;
@ -1539,6 +1539,7 @@ in
      parse_duration = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".parse_duration."2.1.1" { inherit profileName; }).out;
      ${ if rootFeatures' ? "garage/default" || rootFeatures' ? "garage/metrics" || rootFeatures' ? "garage/prometheus" then "prometheus" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".prometheus."0.13.0" { inherit profileName; }).out;
      rand = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rand."0.8.5" { inherit profileName; }).out;
+      rmp_serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rmp-serde."0.15.5" { inherit profileName; }).out;
      serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
      serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
      structopt = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".structopt."0.3.26" { inherit profileName; }).out;
@ -1562,13 +1563,13 @@ in
    };
  });
  
-  "unknown".garage_api."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_api."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_api";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/api");
    features = builtins.concatLists [
-      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v") "k2v")
+      (lib.optional (rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v") "k2v")
      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/metrics" || rootFeatures' ? "garage_api/metrics") "metrics")
      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/metrics" || rootFeatures' ? "garage_api/metrics" || rootFeatures' ? "garage_api/opentelemetry-prometheus") "opentelemetry-prometheus")
      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/metrics" || rootFeatures' ? "garage_api/metrics" || rootFeatures' ? "garage_api/prometheus") "prometheus")
@ -1583,11 +1584,11 @@ in
      form_urlencoded = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".form_urlencoded."1.0.1" { inherit profileName; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_block = (rustPackages."unknown".garage_block."0.8.1" { inherit profileName; }).out;
-      garage_model = (rustPackages."unknown".garage_model."0.8.1" { inherit profileName; }).out;
-      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.1" { inherit profileName; }).out;
-      garage_table = (rustPackages."unknown".garage_table."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_block = (rustPackages."unknown".garage_block."0.8.0" { inherit profileName; }).out;
+      garage_model = (rustPackages."unknown".garage_model."0.8.0" { inherit profileName; }).out;
+      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.0" { inherit profileName; }).out;
+      garage_table = (rustPackages."unknown".garage_table."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      hmac = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hmac."0.12.1" { inherit profileName; }).out;
      http = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".http."0.2.8" { inherit profileName; }).out;
@ -1616,9 +1617,9 @@ in
    };
  });
  
-  "unknown".garage_block."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_block."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_block";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/block");
    features = builtins.concatLists [
@ -1631,13 +1632,14 @@ in
      bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".bytes."1.2.0" { inherit profileName; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_db = (rustPackages."unknown".garage_db."0.8.1" { inherit profileName; }).out;
-      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.1" { inherit profileName; }).out;
-      garage_table = (rustPackages."unknown".garage_table."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_db = (rustPackages."unknown".garage_db."0.8.0" { inherit profileName; }).out;
+      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.0" { inherit profileName; }).out;
+      garage_table = (rustPackages."unknown".garage_table."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      opentelemetry = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".opentelemetry."0.17.0" { inherit profileName; }).out;
      rand = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rand."0.8.5" { inherit profileName; }).out;
+      rmp_serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rmp-serde."0.15.5" { inherit profileName; }).out;
      serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
      serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
      tokio = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tokio."1.17.0" { inherit profileName; }).out;
@ -1647,9 +1649,9 @@ in
    };
  });
  
-  "unknown".garage_db."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_db."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_db";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/db");
    features = builtins.concatLists [
@ -1679,14 +1681,14 @@ in
    };
  });
  
-  "unknown".garage_model."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_model."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_model";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/model");
    features = builtins.concatLists [
      [ "default" ]
-      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v" || rootFeatures' ? "garage_model/k2v") "k2v")
+      (lib.optional (rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v" || rootFeatures' ? "garage_model/k2v") "k2v")
      (lib.optional (rootFeatures' ? "garage/lmdb" || rootFeatures' ? "garage_model/lmdb") "lmdb")
      [ "sled" ]
      (lib.optional (rootFeatures' ? "garage/sqlite" || rootFeatures' ? "garage_model/sqlite") "sqlite")
@ -1699,15 +1701,16 @@ in
      err_derive = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".err-derive."0.3.1" { profileName = "__noProfile"; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_block = (rustPackages."unknown".garage_block."0.8.1" { inherit profileName; }).out;
-      garage_db = (rustPackages."unknown".garage_db."0.8.1" { inherit profileName; }).out;
-      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.1" { inherit profileName; }).out;
-      garage_table = (rustPackages."unknown".garage_table."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_block = (rustPackages."unknown".garage_block."0.8.0" { inherit profileName; }).out;
+      garage_db = (rustPackages."unknown".garage_db."0.8.0" { inherit profileName; }).out;
+      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.0" { inherit profileName; }).out;
+      garage_table = (rustPackages."unknown".garage_table."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      netapp = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".netapp."0.5.2" { inherit profileName; }).out;
      opentelemetry = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".opentelemetry."0.17.0" { inherit profileName; }).out;
      rand = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rand."0.8.5" { inherit profileName; }).out;
+      rmp_serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rmp-serde."0.15.5" { inherit profileName; }).out;
      serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
      serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
      tokio = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tokio."1.17.0" { inherit profileName; }).out;
@ -1716,9 +1719,9 @@ in
    };
  });
  
-  "unknown".garage_rpc."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_rpc."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_rpc";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/rpc");
    features = builtins.concatLists [
@ -1738,7 +1741,7 @@ in
      ${ if rootFeatures' ? "garage/consul-discovery" || rootFeatures' ? "garage_rpc/consul-discovery" || rootFeatures' ? "garage_rpc/err-derive" then "err_derive" else null } = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".err-derive."0.3.1" { profileName = "__noProfile"; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      gethostname = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".gethostname."0.2.3" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      ${ if rootFeatures' ? "garage/kubernetes-discovery" || rootFeatures' ? "garage_rpc/k8s-openapi" || rootFeatures' ? "garage_rpc/kubernetes-discovery" then "k8s_openapi" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".k8s-openapi."0.16.0" { inherit profileName; }).out;
@ -1749,6 +1752,7 @@ in
      pnet_datalink = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".pnet_datalink."0.28.0" { inherit profileName; }).out;
      rand = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rand."0.8.5" { inherit profileName; }).out;
      ${ if rootFeatures' ? "garage/consul-discovery" || rootFeatures' ? "garage_rpc/consul-discovery" || rootFeatures' ? "garage_rpc/reqwest" then "reqwest" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".reqwest."0.11.12" { inherit profileName; }).out;
+      rmp_serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rmp-serde."0.15.5" { inherit profileName; }).out;
      ${ if rootFeatures' ? "garage/kubernetes-discovery" || rootFeatures' ? "garage_rpc/kubernetes-discovery" || rootFeatures' ? "garage_rpc/schemars" then "schemars" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".schemars."0.8.8" { inherit profileName; }).out;
      serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
      serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
@ -1759,24 +1763,24 @@ in
    };
  });
  
-  "unknown".garage_table."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_table."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_table";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/table");
    dependencies = {
-      arc_swap = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".arc-swap."1.5.0" { inherit profileName; }).out;
      async_trait = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".async-trait."0.1.52" { profileName = "__noProfile"; }).out;
      bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".bytes."1.2.0" { inherit profileName; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
      futures_util = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures-util."0.3.21" { inherit profileName; }).out;
-      garage_db = (rustPackages."unknown".garage_db."0.8.1" { inherit profileName; }).out;
-      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_db = (rustPackages."unknown".garage_db."0.8.0" { inherit profileName; }).out;
+      garage_rpc = (rustPackages."unknown".garage_rpc."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
      hexdump = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hexdump."0.1.1" { inherit profileName; }).out;
      opentelemetry = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".opentelemetry."0.17.0" { inherit profileName; }).out;
      rand = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rand."0.8.5" { inherit profileName; }).out;
+      rmp_serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rmp-serde."0.15.5" { inherit profileName; }).out;
      serde = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde."1.0.137" { inherit profileName; }).out;
      serde_bytes = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".serde_bytes."0.11.5" { inherit profileName; }).out;
      tokio = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tokio."1.17.0" { inherit profileName; }).out;
@ -1784,13 +1788,13 @@ in
    };
  });
  
-  "unknown".garage_util."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_util."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_util";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/util");
    features = builtins.concatLists [
-      (lib.optional (rootFeatures' ? "garage/default" || rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v" || rootFeatures' ? "garage_model/k2v" || rootFeatures' ? "garage_util/k2v") "k2v")
+      (lib.optional (rootFeatures' ? "garage/k2v" || rootFeatures' ? "garage_api/k2v" || rootFeatures' ? "garage_model/k2v" || rootFeatures' ? "garage_util/k2v") "k2v")
    ];
    dependencies = {
      arc_swap = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".arc-swap."1.5.0" { inherit profileName; }).out;
@ -1801,10 +1805,9 @@ in
      digest = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".digest."0.10.3" { inherit profileName; }).out;
      err_derive = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".err-derive."0.3.1" { profileName = "__noProfile"; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
-      garage_db = (rustPackages."unknown".garage_db."0.8.1" { inherit profileName; }).out;
+      garage_db = (rustPackages."unknown".garage_db."0.8.0" { inherit profileName; }).out;
      git_version = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".git-version."0.3.5" { inherit profileName; }).out;
      hex = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hex."0.4.3" { inherit profileName; }).out;
-      hexdump = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hexdump."0.1.1" { inherit profileName; }).out;
      http = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".http."0.2.8" { inherit profileName; }).out;
      hyper = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hyper."0.14.18" { inherit profileName; }).out;
      lazy_static = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".lazy_static."1.4.0" { inherit profileName; }).out;
@ -1820,23 +1823,20 @@ in
      tracing = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tracing."0.1.32" { inherit profileName; }).out;
      xxhash_rust = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".xxhash-rust."0.8.4" { inherit profileName; }).out;
    };
-    devDependencies = {
-      mktemp = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".mktemp."0.4.1" { inherit profileName; }).out;
-    };
  });
  
-  "unknown".garage_web."0.8.1" = overridableMkRustCrate (profileName: rec {
+  "unknown".garage_web."0.8.0" = overridableMkRustCrate (profileName: rec {
    name = "garage_web";
-    version = "0.8.1";
+    version = "0.8.0";
    registry = "unknown";
    src = fetchCrateLocal (workspaceSrc + "/src/web");
    dependencies = {
      err_derive = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".err-derive."0.3.1" { profileName = "__noProfile"; }).out;
      futures = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".futures."0.3.21" { inherit profileName; }).out;
-      garage_api = (rustPackages."unknown".garage_api."0.8.1" { inherit profileName; }).out;
-      garage_model = (rustPackages."unknown".garage_model."0.8.1" { inherit profileName; }).out;
-      garage_table = (rustPackages."unknown".garage_table."0.8.1" { inherit profileName; }).out;
-      garage_util = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      garage_api = (rustPackages."unknown".garage_api."0.8.0" { inherit profileName; }).out;
+      garage_model = (rustPackages."unknown".garage_model."0.8.0" { inherit profileName; }).out;
+      garage_table = (rustPackages."unknown".garage_table."0.8.0" { inherit profileName; }).out;
+      garage_util = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      http = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".http."0.2.8" { inherit profileName; }).out;
      hyper = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hyper."0.14.18" { inherit profileName; }).out;
      opentelemetry = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".opentelemetry."0.17.0" { inherit profileName; }).out;
@ -2450,7 +2450,7 @@ in
    dependencies = {
      base64 = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".base64."0.13.0" { inherit profileName; }).out;
      ${ if rootFeatures' ? "k2v-client/clap" || rootFeatures' ? "k2v-client/cli" then "clap" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".clap."3.1.18" { inherit profileName; }).out;
-      ${ if rootFeatures' ? "k2v-client/cli" || rootFeatures' ? "k2v-client/garage_util" then "garage_util" else null } = (rustPackages."unknown".garage_util."0.8.1" { inherit profileName; }).out;
+      ${ if rootFeatures' ? "k2v-client/cli" || rootFeatures' ? "k2v-client/garage_util" then "garage_util" else null } = (rustPackages."unknown".garage_util."0.8.0" { inherit profileName; }).out;
      http = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".http."0.2.8" { inherit profileName; }).out;
      log = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".log."0.4.16" { inherit profileName; }).out;
      rusoto_core = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rusoto_core."0.48.0" { inherit profileName; }).out;
--- a/doc/book/connect/apps/index.md
+++ b/doc/book/connect/apps/index.md
@ -8,7 +8,7 @@ In this section, we cover the following web applications:
 | Name | Status | Note |
 |------|--------|------|
 | [Nextcloud](#nextcloud)     | ✅       |  Both Primary Storage and External Storage are supported    |
-| [Peertube](#peertube)     | ✅       | Supported with the website endpoint, proxifying private videos unsupported     |
+| [Peertube](#peertube)     | ✅       | Must be configured with the website endpoint     |
 | [Mastodon](#mastodon)     | ✅       | Natively supported    |
 | [Matrix](#matrix)     | ✅       |  Tested with `synapse-s3-storage-provider`    |
 | [Pixelfed](#pixelfed)     | ❓       |  Not yet tested    |
@ -128,10 +128,6 @@ In other words, Peertube is only responsible of the "control plane" and offload
 In return, this system is a bit harder to configure.
 We show how it is still possible to configure Garage with Peertube, allowing you to spread the load and the bandwidth usage on the Garage cluster.

-Starting from version 5.0, Peertube also supports improving the security for private videos by not exposing them directly
-but relying on a single control point in the Peertube instance. This is based on S3 per-object and prefix ACL, which are not currently supported
-in Garage, so this feature is unsupported. While this technically impedes security for private videos, it is not a blocking issue and could be
-a reasonable trade-off for some instances.

 ### Create resources in Garage

@ -199,11 +195,6 @@ object_storage:

  max_upload_part: 2GB

-  proxy:
-    # You may enable this feature, yet it will not provide any security benefit, so
-    # you should rather benefit from Garage public endpoint for all videos
-    proxify_private_files: false
-
  streaming_playlists:
    bucket_name: 'peertube-playlist'

--- a/doc/book/development/devenv.md
+++ b/doc/book/development/devenv.md
@ -39,7 +39,7 @@ Now you can enter our nix-shell, all the required packages will be downloaded bu
 nix-shell
 ```

-You can use the traditional Rust development workflow:
+You can use the traditionnal Rust development workflow:

 ```bash
 cargo build  # compile the project
--- a/doc/book/reference-manual/configuration.md
+++ b/doc/book/reference-manual/configuration.md
@ -96,7 +96,7 @@ Performance characteristics of the different DB engines are as follows:

 - Sled: the default database engine, which tends to produce
  large data files and also has performance issues, especially when the metadata folder
-  is on a traditional HDD and not on SSD.
+  is on a traditionnal HDD and not on SSD.
 - LMDB: the recommended alternative on 64-bit systems,
  much more space-efficiant and slightly faster. Note that the data format of LMDB is not portable
  between architectures, so for instance the Garage database of an x86-64
@ -267,10 +267,6 @@ This key should be specified here in the form of a 32-byte hex-encoded
 random string. Such a string can be generated with a command
 such as `openssl rand -hex 32`.

-### `rpc_secret_file`
-
-Like `rpc_secret` above, just that this is the path to a file that Garage will try to read the secret from.
-
 ### `rpc_bind_addr`

 The address and port on which to bind for inter-cluster communcations
--- a/flake.lock
+++ b/flake.lock
@ -55,21 +55,6 @@
        "type": "github"
      }
    },
-    "flake-utils_2": {
-      "locked": {
-        "lastModified": 1667395993,
-        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
    "nixpkgs": {
      "locked": {
        "lastModified": 1665657542,
@ -89,7 +74,6 @@
    "root": {
      "inputs": {
        "cargo2nix": "cargo2nix",
-        "flake-utils": "flake-utils_2",
        "nixpkgs": "nixpkgs"
      }
    },
--- a/flake.nix
+++ b/flake.nix
@ -7,30 +7,22 @@
    url = "github:Alexis211/cargo2nix/a7a61179b66054904ef6a195d8da736eaaa06c36";
    inputs.nixpkgs.follows = "nixpkgs";
  };
-  inputs.flake-utils.url = "github:numtide/flake-utils";

-  outputs = { self, nixpkgs, cargo2nix, flake-utils }:
-    let
+  outputs = { self, nixpkgs, cargo2nix }: let
    git_version = self.lastModifiedDate;
    compile = import ./nix/compile.nix;
-    in flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        packages = {
+    forAllSystems = nixpkgs.lib.genAttrs nixpkgs.lib.systems.flakeExposed;
+  in
+  {
+    packages = forAllSystems (system: {
      default = (compile {
        inherit system git_version;
        pkgsSrc = nixpkgs;
        cargo2nixOverlay = cargo2nix.overlays.default;
        release = true;
-          }).workspace.garage { compileMode = "build"; };
+      }).workspace.garage {
+        compileMode = "build";
      };
-        devShell = ((compile {
-          inherit system git_version;
-          pkgsSrc = nixpkgs;
-          cargo2nixOverlay = cargo2nix.overlays.default;
-          release = false;
-        }).workspaceShell {
-          packages = [ pkgs.rustfmt cargo2nix.packages.${system}.default ];
-        });
    });
+  };
 }
--- a/src/api/Cargo.toml
+++ b/src/api/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_api"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,11 +14,11 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_model = { version = "0.8.1", path = "../model" }
-garage_table = { version = "0.8.1", path = "../table" }
-garage_block = { version = "0.8.1", path = "../block" }
-garage_util = { version = "0.8.1", path = "../util" }
-garage_rpc = { version = "0.8.1", path = "../rpc" }
+garage_model = { version = "0.8.0", path = "../model" }
+garage_table = { version = "0.8.0", path = "../table" }
+garage_block = { version = "0.8.0", path = "../block" }
+garage_util = { version = "0.8.0", path = "../util" }
+garage_rpc = { version = "0.8.0", path = "../rpc" }

 async-trait = "0.1.7"
 base64 = "0.13"
--- a/src/api/router_macros.rs
+++ b/src/api/router_macros.rs
@ -145,7 +145,6 @@ macro_rules! generateQueryParameters {
    ) => {
        #[derive(Debug)]
        #[allow(non_camel_case_types)]
-        #[allow(clippy::upper_case_acronyms)]
        enum Keyword {
            EMPTY,
            $( $kw_name, )*
--- a/src/api/s3/put.rs
+++ b/src/api/s3/put.rs
@ -119,17 +119,6 @@ pub(crate) async fn save_stream<S: Stream<Item = Result<Bytes, Error>> + Unpin>(
 		return Ok((version_uuid, data_md5sum_hex));
 	}

-	// The following consists in many steps that can each fail.
-	// Keep track that some cleanup will be needed if things fail
-	// before everything is finished (cleanup is done using the Drop trait).
-	let mut interrupted_cleanup = InterruptedCleanup(Some((
-		garage.clone(),
-		bucket.id,
-		key.into(),
-		version_uuid,
-		version_timestamp,
-	)));
-
 	// Write version identifier in object table so that we have a trace
 	// that we are uploading something
 	let mut object_version = ObjectVersion {
@ -150,6 +139,7 @@ pub(crate) async fn save_stream<S: Stream<Item = Result<Bytes, Error>> + Unpin>(
 	// Transfer data and verify checksum
 	let first_block_hash = async_blake2sum(first_block.clone()).await;

+	let tx_result = (|| async {
 		let (total_size, data_md5sum, data_sha256sum) = read_and_put_blocks(
 			&garage,
 			&version,
@ -169,8 +159,24 @@ pub(crate) async fn save_stream<S: Stream<Item = Result<Bytes, Error>> + Unpin>(

 		check_quotas(&garage, bucket, key, total_size).await?;

+		Ok((total_size, data_md5sum))
+	})()
+	.await;
+
+	// If something went wrong, clean up
+	let (total_size, md5sum_arr) = match tx_result {
+		Ok(rv) => rv,
+		Err(e) => {
+			// Mark object as aborted, this will free the blocks further down
+			object_version.state = ObjectVersionState::Aborted;
+			let object = Object::new(bucket.id, key.into(), vec![object_version.clone()]);
+			garage.object_table.insert(&object).await?;
+			return Err(e);
+		}
+	};
+
 	// Save final object state, marked as Complete
-	let md5sum_hex = hex::encode(data_md5sum);
+	let md5sum_hex = hex::encode(md5sum_arr);
 	object_version.state = ObjectVersionState::Complete(ObjectVersionData::FirstBlock(
 		ObjectVersionMeta {
 			headers,
@ -182,10 +188,6 @@ pub(crate) async fn save_stream<S: Stream<Item = Result<Bytes, Error>> + Unpin>(
 	let object = Object::new(bucket.id, key.into(), vec![object_version]);
 	garage.object_table.insert(&object).await?;

-	// We were not interrupted, everything went fine.
-	// We won't have to clean up on drop.
-	interrupted_cleanup.cancel();
-
 	Ok((version_uuid, md5sum_hex))
 }

@ -424,33 +426,6 @@ pub fn put_response(version_uuid: Uuid, md5sum_hex: String) -> Response<Body> {
 		.unwrap()
 }

-struct InterruptedCleanup(Option<(Arc<Garage>, Uuid, String, Uuid, u64)>);
-
-impl InterruptedCleanup {
-	fn cancel(&mut self) {
-		drop(self.0.take());
-	}
-}
-impl Drop for InterruptedCleanup {
-	fn drop(&mut self) {
-		if let Some((garage, bucket_id, key, version_uuid, version_ts)) = self.0.take() {
-			tokio::spawn(async move {
-				let object_version = ObjectVersion {
-					uuid: version_uuid,
-					timestamp: version_ts,
-					state: ObjectVersionState::Aborted,
-				};
-				let object = Object::new(bucket_id, key, vec![object_version]);
-				if let Err(e) = garage.object_table.insert(&object).await {
-					warn!("Cannot cleanup after aborted PutObject: {}", e);
-				}
-			});
-		}
-	}
-}
-
-// ----
-
 pub async fn handle_create_multipart_upload(
 	garage: Arc<Garage>,
 	req: &Request<Body>,
--- a/src/block/Cargo.toml
+++ b/src/block/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_block"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,10 +14,10 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_db = { version = "0.8.1", path = "../db" }
-garage_rpc = { version = "0.8.1", path = "../rpc" }
-garage_util = { version = "0.8.1", path = "../util" }
-garage_table = { version = "0.8.1", path = "../table" }
+garage_db = { version = "0.8.0", path = "../db" }
+garage_rpc = { version = "0.8.0", path = "../rpc" }
+garage_util = { version = "0.8.0", path = "../util" }
+garage_table = { version = "0.8.0", path = "../table" }

 opentelemetry = "0.17"

@ -31,6 +31,7 @@ rand = "0.8"
 async-compression = { version = "0.3", features = ["tokio", "zstd"] }
 zstd = { version = "0.9", default-features = false }

+rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"

--- a/src/block/manager.rs
+++ b/src/block/manager.rs
@ -3,10 +3,8 @@ use std::pin::Pin;
 use std::sync::Arc;
 use std::time::Duration;

-use arc_swap::ArcSwapOption;
 use async_trait::async_trait;
 use bytes::Bytes;
-use rand::prelude::*;
 use serde::{Deserialize, Serialize};

 use futures::Stream;
@ -24,12 +22,9 @@ use garage_rpc::rpc_helper::netapp::stream::{stream_asyncread, ByteStream};

 use garage_db as db;

-use garage_util::background::{vars, BackgroundRunner};
 use garage_util::data::*;
 use garage_util::error::*;
 use garage_util::metrics::RecordDuration;
-use garage_util::persister::PersisterShared;
-use garage_util::time::msec_to_rfc3339;

 use garage_rpc::rpc_helper::OrderTag;
 use garage_rpc::system::System;
@ -92,17 +87,7 @@ pub struct BlockManager {

 	pub(crate) metrics: BlockManagerMetrics,

-	pub scrub_persister: PersisterShared<ScrubWorkerPersisted>,
-	tx_scrub_command: ArcSwapOption<mpsc::Sender<ScrubWorkerCommand>>,
-}
-
-#[derive(Serialize, Deserialize, Clone, Debug)]
-pub struct BlockResyncErrorInfo {
-	pub hash: Hash,
-	pub refcount: u64,
-	pub error_count: u64,
-	pub last_try: u64,
-	pub next_try: u64,
+	tx_scrub_command: mpsc::Sender<ScrubWorkerCommand>,
 }

 // This custom struct contains functions that must only be ran
@ -129,14 +114,9 @@ impl BlockManager {
 			.netapp
 			.endpoint("garage_block/manager.rs/Rpc".to_string());

-		let metrics = BlockManagerMetrics::new(
-			compression_level,
-			rc.rc.clone(),
-			resync.queue.clone(),
-			resync.errors.clone(),
-		);
+		let metrics = BlockManagerMetrics::new(resync.queue.clone(), resync.errors.clone());

-		let scrub_persister = PersisterShared::new(&system.metadata_dir, "scrub_info");
+		let (scrub_tx, scrub_rx) = mpsc::channel(1);

 		let block_manager = Arc::new(Self {
 			replication,
@ -148,46 +128,21 @@ impl BlockManager {
 			system,
 			endpoint,
 			metrics,
-			scrub_persister,
-			tx_scrub_command: ArcSwapOption::new(None),
+			tx_scrub_command: scrub_tx,
 		});
 		block_manager.endpoint.set_handler(block_manager.clone());

-		block_manager
-	}
-
-	pub fn spawn_workers(self: &Arc<Self>, bg: &BackgroundRunner) {
 		// Spawn a bunch of resync workers
 		for index in 0..MAX_RESYNC_WORKERS {
-			let worker = ResyncWorker::new(index, self.clone());
-			bg.spawn_worker(worker);
+			let worker = ResyncWorker::new(index, block_manager.clone());
+			block_manager.system.background.spawn_worker(worker);
 		}

 		// Spawn scrub worker
-		let (scrub_tx, scrub_rx) = mpsc::channel(1);
-		self.tx_scrub_command.store(Some(Arc::new(scrub_tx)));
-		bg.spawn_worker(ScrubWorker::new(
-			self.clone(),
-			scrub_rx,
-			self.scrub_persister.clone(),
-		));
-	}
+		let scrub_worker = ScrubWorker::new(block_manager.clone(), scrub_rx);
+		block_manager.system.background.spawn_worker(scrub_worker);

-	pub fn register_bg_vars(&self, vars: &mut vars::BgVars) {
-		self.resync.register_bg_vars(vars);
-
-		vars.register_rw(
-			&self.scrub_persister,
-			"scrub-tranquility",
-			|p| p.get_with(|x| x.tranquility),
-			|p, tranquility| p.set_with(|x| x.tranquility = tranquility),
-		);
-		vars.register_ro(&self.scrub_persister, "scrub-last-completed", |p| {
-			p.get_with(|x| msec_to_rfc3339(x.time_last_complete_scrub))
-		});
-		vars.register_ro(&self.scrub_persister, "scrub-corruptions_detected", |p| {
-			p.get_with(|x| x.corruptions_detected)
-		});
+		block_manager
 	}

 	/// Ask nodes that might have a (possibly compressed) block for it
@ -354,42 +309,9 @@ impl BlockManager {
 		Ok(self.rc.rc.len()?)
 	}

-	/// Get number of items in the refcount table
-	pub fn rc_fast_len(&self) -> Result<Option<usize>, Error> {
-		Ok(self.rc.rc.fast_len()?)
-	}
-
 	/// Send command to start/stop/manager scrub worker
-	pub async fn send_scrub_command(&self, cmd: ScrubWorkerCommand) -> Result<(), Error> {
-		let tx = self.tx_scrub_command.load();
-		let tx = tx.as_ref().ok_or_message("scrub worker is not running")?;
-		tx.send(cmd).await.ok_or_message("send error")?;
-		Ok(())
-	}
-
-	/// Get the reference count of a block
-	pub fn get_block_rc(&self, hash: &Hash) -> Result<u64, Error> {
-		Ok(self.rc.get_block_rc(hash)?.as_u64())
-	}
-
-	/// List all resync errors
-	pub fn list_resync_errors(&self) -> Result<Vec<BlockResyncErrorInfo>, Error> {
-		let mut blocks = Vec::with_capacity(self.resync.errors.len());
-		for ent in self.resync.errors.iter()? {
-			let (hash, cnt) = ent?;
-			let cnt = ErrorCounter::decode(&cnt);
-			blocks.push(BlockResyncErrorInfo {
-				hash: Hash::try_from(&hash).unwrap(),
-				refcount: 0,
-				error_count: cnt.errors,
-				last_try: cnt.last_try,
-				next_try: cnt.next_try(),
-			});
-		}
-		for block in blocks.iter_mut() {
-			block.refcount = self.get_block_rc(&block.hash)?;
-		}
-		Ok(blocks)
+	pub async fn send_scrub_command(&self, cmd: ScrubWorkerCommand) {
+		let _ = self.tx_scrub_command.send(cmd).await;
 	}

 	//// ----- Managing the reference counter ----
@ -681,21 +603,14 @@ impl BlockManagerLocked {
 			}
 		};

-		let mut path_tmp = path.clone();
-		let tmp_extension = format!("tmp{}", hex::encode(thread_rng().gen::<[u8; 4]>()));
-		path_tmp.set_extension(tmp_extension);
-
-		let mut delete_on_drop = DeleteOnDrop(Some(path_tmp.clone()));
-
-		let mut f = fs::File::create(&path_tmp).await?;
+		let mut path2 = path.clone();
+		path2.set_extension("tmp");
+		let mut f = fs::File::create(&path2).await?;
 		f.write_all(data).await?;
 		f.sync_all().await?;
 		drop(f);

-		fs::rename(path_tmp, path).await?;
-
-		delete_on_drop.cancel();
-
+		fs::rename(path2, path).await?;
 		if let Some(to_delete) = to_delete {
 			fs::remove_file(to_delete).await?;
 		}
@ -761,23 +676,3 @@ async fn read_stream_to_end(mut stream: ByteStream) -> Result<Bytes, Error> {
 		.concat()
 		.into())
 }
-
-struct DeleteOnDrop(Option<PathBuf>);
-
-impl DeleteOnDrop {
-	fn cancel(&mut self) {
-		drop(self.0.take());
-	}
-}
-
-impl Drop for DeleteOnDrop {
-	fn drop(&mut self) {
-		if let Some(path) = self.0.take() {
-			tokio::spawn(async move {
-				if let Err(e) = fs::remove_file(&path).await {
-					debug!("DeleteOnDrop failed for {}: {}", path.display(), e);
-				}
-			});
-		}
-	}
-}
--- a/src/block/metrics.rs
+++ b/src/block/metrics.rs
@ -1,12 +1,9 @@
 use opentelemetry::{global, metrics::*};

-use garage_db as db;
 use garage_db::counted_tree_hack::CountedTree;

 /// TableMetrics reference all counter used for metrics
 pub struct BlockManagerMetrics {
-	pub(crate) _compression_level: ValueObserver<u64>,
-	pub(crate) _rc_size: ValueObserver<u64>,
 	pub(crate) _resync_queue_len: ValueObserver<u64>,
 	pub(crate) _resync_errored_blocks: ValueObserver<u64>,

@ -26,31 +23,9 @@ pub struct BlockManagerMetrics {
 }

 impl BlockManagerMetrics {
-	pub fn new(
-		compression_level: Option<i32>,
-		rc_tree: db::Tree,
-		resync_queue: CountedTree,
-		resync_errors: CountedTree,
-	) -> Self {
+	pub fn new(resync_queue: CountedTree, resync_errors: CountedTree) -> Self {
 		let meter = global::meter("garage_model/block");
 		Self {
-			_compression_level: meter
-				.u64_value_observer("block.compression_level", move |observer| {
-					match compression_level {
-						Some(v) => observer.observe(v as u64, &[]),
-						None => observer.observe(0 as u64, &[]),
-					}
-				})
-				.with_description("Garage compression level for node")
-				.init(),
-			_rc_size: meter
-				.u64_value_observer("block.rc_size", move |observer| {
-					if let Ok(Some(v)) = rc_tree.fast_len() {
-						observer.observe(v as u64, &[])
-					}
-				})
-				.with_description("Number of blocks known to the reference counter")
-				.init(),
 			_resync_queue_len: meter
 				.u64_value_observer("block.resync_queue_length", move |observer| {
 					observer.observe(resync_queue.len() as u64, &[])
--- a/src/block/rc.rs
+++ b/src/block/rc.rs
@ -169,11 +169,4 @@ impl RcEntry {
 	pub(crate) fn is_needed(&self) -> bool {
 		!self.is_deletable()
 	}
-
-	pub(crate) fn as_u64(&self) -> u64 {
-		match self {
-			RcEntry::Present { count } => *count,
-			_ => 0,
-		}
-	}
 }
--- a/src/block/repair.rs
+++ b/src/block/repair.rs
@ -13,7 +13,7 @@ use tokio::sync::watch;
 use garage_util::background::*;
 use garage_util::data::*;
 use garage_util::error::*;
-use garage_util::persister::PersisterShared;
+use garage_util::persister::Persister;
 use garage_util::time::*;
 use garage_util::tranquilizer::Tranquilizer;

@ -53,7 +53,7 @@ impl Worker for RepairWorker {
 		"Block repair worker".into()
 	}

-	fn status(&self) -> WorkerStatus {
+	fn info(&self) -> Option<String> {
 		match self.block_iter.as_ref() {
 			None => {
 				let idx_bytes = self
@ -66,20 +66,9 @@ impl Worker for RepairWorker {
 				} else {
 					idx_bytes
 				};
-				WorkerStatus {
-					progress: Some("0.00%".into()),
-					freeform: vec![format!(
-						"Currently in phase 1, iterator position: {}",
-						hex::encode(idx_bytes)
-					)],
-					..Default::default()
+				Some(format!("Phase 1: {}", hex::encode(idx_bytes)))
 			}
-			}
-			Some(bi) => WorkerStatus {
-				progress: Some(format!("{:.2}%", bi.progress() * 100.)),
-				freeform: vec!["Currently in phase 2".into()],
-				..Default::default()
-			},
+			Some(bi) => Some(format!("Phase 2: {:.2}% done", bi.progress() * 100.)),
 		}
 	}

@ -148,7 +137,7 @@ impl Worker for RepairWorker {
 		}
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
 		unreachable!()
 	}
 }
@ -168,24 +157,15 @@ pub struct ScrubWorker {
 	work: ScrubWorkerState,
 	tranquilizer: Tranquilizer,

-	persister: PersisterShared<ScrubWorkerPersisted>,
+	persister: Persister<ScrubWorkerPersisted>,
+	persisted: ScrubWorkerPersisted,
 }

 #[derive(Serialize, Deserialize)]
-pub struct ScrubWorkerPersisted {
-	pub tranquility: u32,
-	pub(crate) time_last_complete_scrub: u64,
-	pub(crate) corruptions_detected: u64,
-}
-impl garage_util::migrate::InitialFormat for ScrubWorkerPersisted {}
-impl Default for ScrubWorkerPersisted {
-	fn default() -> Self {
-		ScrubWorkerPersisted {
-			time_last_complete_scrub: 0,
-			tranquility: INITIAL_SCRUB_TRANQUILITY,
-			corruptions_detected: 0,
-		}
-	}
+struct ScrubWorkerPersisted {
+	tranquility: u32,
+	time_last_complete_scrub: u64,
+	corruptions_detected: u64,
 }

 enum ScrubWorkerState {
@ -206,20 +186,27 @@ pub enum ScrubWorkerCommand {
 	Pause(Duration),
 	Resume,
 	Cancel,
+	SetTranquility(u32),
 }

 impl ScrubWorker {
-	pub(crate) fn new(
-		manager: Arc<BlockManager>,
-		rx_cmd: mpsc::Receiver<ScrubWorkerCommand>,
-		persister: PersisterShared<ScrubWorkerPersisted>,
-	) -> Self {
+	pub fn new(manager: Arc<BlockManager>, rx_cmd: mpsc::Receiver<ScrubWorkerCommand>) -> Self {
+		let persister = Persister::new(&manager.system.metadata_dir, "scrub_info");
+		let persisted = match persister.load() {
+			Ok(v) => v,
+			Err(_) => ScrubWorkerPersisted {
+				time_last_complete_scrub: 0,
+				tranquility: INITIAL_SCRUB_TRANQUILITY,
+				corruptions_detected: 0,
+			},
+		};
 		Self {
 			manager,
 			rx_cmd,
 			work: ScrubWorkerState::Finished,
 			tranquilizer: Tranquilizer::new(30),
 			persister,
+			persisted,
 		}
 	}

@ -268,6 +255,12 @@ impl ScrubWorker {
 					}
 				}
 			}
+			ScrubWorkerCommand::SetTranquility(t) => {
+				self.persisted.tranquility = t;
+				if let Err(e) = self.persister.save_async(&self.persisted).await {
+					error!("Could not save new tranquilitiy value: {}", e);
+				}
+			}
 		}
 	}
 }
@ -278,37 +271,29 @@ impl Worker for ScrubWorker {
 		"Block scrub worker".into()
 	}

-	fn status(&self) -> WorkerStatus {
-		let (corruptions_detected, tranquility, time_last_complete_scrub) =
-			self.persister.get_with(|p| {
-				(
-					p.corruptions_detected,
-					p.tranquility,
-					p.time_last_complete_scrub,
-				)
-			});
-
-		let mut s = WorkerStatus {
-			persistent_errors: Some(corruptions_detected),
-			tranquility: Some(tranquility),
-			..Default::default()
-		};
-		match &self.work {
-			ScrubWorkerState::Running(bsi) => {
-				s.progress = Some(format!("{:.2}%", bsi.progress() * 100.));
-			}
+	fn info(&self) -> Option<String> {
+		let s = match &self.work {
+			ScrubWorkerState::Running(bsi) => format!(
+				"{:.2}% done (tranquility = {})",
+				bsi.progress() * 100.,
+				self.persisted.tranquility
+			),
 			ScrubWorkerState::Paused(bsi, rt) => {
-				s.progress = Some(format!("{:.2}%", bsi.progress() * 100.));
-				s.freeform = vec![format!("Scrub paused, resumes at {}", msec_to_rfc3339(*rt))];
+				format!(
+					"Paused, {:.2}% done, resumes at {}",
+					bsi.progress() * 100.,
+					msec_to_rfc3339(*rt)
+				)
 			}
-			ScrubWorkerState::Finished => {
-				s.freeform = vec![format!(
-					"Last scrub completed at {}",
-					msec_to_rfc3339(time_last_complete_scrub)
-				)];
-			}
-		}
-		s
+			ScrubWorkerState::Finished => format!(
+				"Last completed scrub: {}",
+				msec_to_rfc3339(self.persisted.time_last_complete_scrub)
+			),
+		};
+		Some(format!(
+			"{} ; corruptions detected: {}",
+			s, self.persisted.corruptions_detected
+		))
 	}

 	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
@ -325,17 +310,18 @@ impl Worker for ScrubWorker {
 					match self.manager.read_block(&hash).await {
 						Err(Error::CorruptData(_)) => {
 							error!("Found corrupt data block during scrub: {:?}", hash);
-							self.persister.set_with(|p| p.corruptions_detected += 1)?;
+							self.persisted.corruptions_detected += 1;
+							self.persister.save_async(&self.persisted).await?;
 						}
 						Err(e) => return Err(e),
 						_ => (),
 					};
 					Ok(self
 						.tranquilizer
-						.tranquilize_worker(self.persister.get_with(|p| p.tranquility)))
+						.tranquilize_worker(self.persisted.tranquility))
 				} else {
-					self.persister
-						.set_with(|p| p.time_last_complete_scrub = now_msec())?;
+					self.persisted.time_last_complete_scrub = now_msec();
+					self.persister.save_async(&self.persisted).await?;
 					self.work = ScrubWorkerState::Finished;
 					self.tranquilizer.clear();
 					Ok(WorkerState::Idle)
@ -345,13 +331,12 @@ impl Worker for ScrubWorker {
 		}
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
 		let (wait_until, command) = match &self.work {
 			ScrubWorkerState::Running(_) => return WorkerState::Busy,
 			ScrubWorkerState::Paused(_, resume_time) => (*resume_time, ScrubWorkerCommand::Resume),
 			ScrubWorkerState::Finished => (
-				self.persister.get_with(|p| p.time_last_complete_scrub)
-					+ SCRUB_INTERVAL.as_millis() as u64,
+				self.persisted.time_last_complete_scrub + SCRUB_INTERVAL.as_millis() as u64,
 				ScrubWorkerCommand::Start,
 			),
 		};
--- a/src/block/resync.rs
+++ b/src/block/resync.rs
@ -3,6 +3,7 @@ use std::convert::TryInto;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;

+use arc_swap::ArcSwap;
 use async_trait::async_trait;
 use serde::{Deserialize, Serialize};

@ -21,7 +22,7 @@ use garage_util::background::*;
 use garage_util::data::*;
 use garage_util::error::*;
 use garage_util::metrics::RecordDuration;
-use garage_util::persister::PersisterShared;
+use garage_util::persister::Persister;
 use garage_util::time::*;
 use garage_util::tranquilizer::Tranquilizer;

@ -48,12 +49,13 @@ const INITIAL_RESYNC_TRANQUILITY: u32 = 2;

 pub struct BlockResyncManager {
 	pub(crate) queue: CountedTree,
-	pub(crate) notify: Arc<Notify>,
+	pub(crate) notify: Notify,
 	pub(crate) errors: CountedTree,

 	busy_set: BusySet,

-	persister: PersisterShared<ResyncPersistedConfig>,
+	persister: Persister<ResyncPersistedConfig>,
+	persisted: ArcSwap<ResyncPersistedConfig>,
 }

 #[derive(Serialize, Deserialize, Clone, Copy)]
@ -61,15 +63,6 @@ struct ResyncPersistedConfig {
 	n_workers: usize,
 	tranquility: u32,
 }
-impl garage_util::migrate::InitialFormat for ResyncPersistedConfig {}
-impl Default for ResyncPersistedConfig {
-	fn default() -> Self {
-		ResyncPersistedConfig {
-			n_workers: 1,
-			tranquility: INITIAL_RESYNC_TRANQUILITY,
-		}
-	}
-}

 enum ResyncIterResult {
 	BusyDidSomething,
@ -97,14 +90,22 @@ impl BlockResyncManager {
 			.expect("Unable to open block_local_resync_errors tree");
 		let errors = CountedTree::new(errors).expect("Could not count block_local_resync_errors");

-		let persister = PersisterShared::new(&system.metadata_dir, "resync_cfg");
+		let persister = Persister::new(&system.metadata_dir, "resync_cfg");
+		let persisted = match persister.load() {
+			Ok(v) => v,
+			Err(_) => ResyncPersistedConfig {
+				n_workers: 1,
+				tranquility: INITIAL_RESYNC_TRANQUILITY,
+			},
+		};

 		Self {
 			queue,
-			notify: Arc::new(Notify::new()),
+			notify: Notify::new(),
 			errors,
 			busy_set: Arc::new(Mutex::new(HashSet::new())),
 			persister,
+			persisted: ArcSwap::new(Arc::new(persisted)),
 		}
 	}

@ -122,56 +123,6 @@ impl BlockResyncManager {
 		Ok(self.errors.len())
 	}

-	/// Clear the error counter for a block and put it in queue immediately
-	pub fn clear_backoff(&self, hash: &Hash) -> Result<(), Error> {
-		let now = now_msec();
-		if let Some(ec) = self.errors.get(hash)? {
-			let mut ec = ErrorCounter::decode(&ec);
-			if ec.errors > 0 {
-				ec.last_try = now - ec.delay_msec();
-				self.errors.insert(hash, ec.encode())?;
-				self.put_to_resync_at(hash, now)?;
-				return Ok(());
-			}
-		}
-		Err(Error::Message(format!(
-			"Block {:?} was not in an errored state",
-			hash
-		)))
-	}
-
-	pub fn register_bg_vars(&self, vars: &mut vars::BgVars) {
-		let notify = self.notify.clone();
-		vars.register_rw(
-			&self.persister,
-			"resync-worker-count",
-			|p| p.get_with(|x| x.n_workers),
-			move |p, n_workers| {
-				if !(1..=MAX_RESYNC_WORKERS).contains(&n_workers) {
-					return Err(Error::Message(format!(
-						"Invalid number of resync workers, must be between 1 and {}",
-						MAX_RESYNC_WORKERS
-					)));
-				}
-				p.set_with(|x| x.n_workers = n_workers)?;
-				notify.notify_waiters();
-				Ok(())
-			},
-		);
-
-		let notify = self.notify.clone();
-		vars.register_rw(
-			&self.persister,
-			"resync-tranquility",
-			|p| p.get_with(|x| x.tranquility),
-			move |p, tranquility| {
-				p.set_with(|x| x.tranquility = tranquility)?;
-				notify.notify_waiters();
-				Ok(())
-			},
-		);
-	}
-
 	// ---- Resync loop ----

 	// This part manages a queue of blocks that need to be
@ -306,7 +257,7 @@ impl BlockResyncManager {

 				if let Err(e) = &res {
 					manager.metrics.resync_error_counter.add(1);
-					error!("Error when resyncing {:?}: {}", hash, e);
+					warn!("Error when resyncing {:?}: {}", hash, e);

 					let err_counter = match self.errors.get(hash.as_slice())? {
 						Some(ec) => ErrorCounter::decode(&ec).add1(now + 1),
@ -466,6 +417,33 @@ impl BlockResyncManager {

 		Ok(())
 	}
+
+	async fn update_persisted(
+		&self,
+		update: impl Fn(&mut ResyncPersistedConfig),
+	) -> Result<(), Error> {
+		let mut cfg: ResyncPersistedConfig = *self.persisted.load().as_ref();
+		update(&mut cfg);
+		self.persister.save_async(&cfg).await?;
+		self.persisted.store(Arc::new(cfg));
+		self.notify.notify_waiters();
+		Ok(())
+	}
+
+	pub async fn set_n_workers(&self, n_workers: usize) -> Result<(), Error> {
+		if !(1..=MAX_RESYNC_WORKERS).contains(&n_workers) {
+			return Err(Error::Message(format!(
+				"Invalid number of resync workers, must be between 1 and {}",
+				MAX_RESYNC_WORKERS
+			)));
+		}
+		self.update_persisted(|cfg| cfg.n_workers = n_workers).await
+	}
+
+	pub async fn set_tranquility(&self, tranquility: u32) -> Result<(), Error> {
+		self.update_persisted(|cfg| cfg.tranquility = tranquility)
+			.await
+	}
 }

 impl Drop for BusyBlock {
@ -480,18 +458,15 @@ pub(crate) struct ResyncWorker {
 	manager: Arc<BlockManager>,
 	tranquilizer: Tranquilizer,
 	next_delay: Duration,
-	persister: PersisterShared<ResyncPersistedConfig>,
 }

 impl ResyncWorker {
 	pub(crate) fn new(index: usize, manager: Arc<BlockManager>) -> Self {
-		let persister = manager.resync.persister.clone();
 		Self {
 			index,
 			manager,
 			tranquilizer: Tranquilizer::new(30),
 			next_delay: Duration::from_secs(10),
-			persister,
 		}
 	}
 }
@ -502,36 +477,39 @@ impl Worker for ResyncWorker {
 		format!("Block resync worker #{}", self.index + 1)
 	}

-	fn status(&self) -> WorkerStatus {
-		let (n_workers, tranquility) = self.persister.get_with(|x| (x.n_workers, x.tranquility));
+	fn info(&self) -> Option<String> {
+		let persisted = self.manager.resync.persisted.load();

-		if self.index >= n_workers {
-			return WorkerStatus {
-				freeform: vec!["This worker is currently disabled".into()],
-				..Default::default()
-			};
+		if self.index >= persisted.n_workers {
+			return Some("(unused)".into());
 		}

-		WorkerStatus {
-			queue_length: Some(self.manager.resync.queue_len().unwrap_or(0) as u64),
-			tranquility: Some(tranquility),
-			persistent_errors: Some(self.manager.resync.errors_len().unwrap_or(0) as u64),
-			..Default::default()
+		let mut ret = vec![];
+		ret.push(format!("tranquility = {}", persisted.tranquility));
+
+		let qlen = self.manager.resync.queue_len().unwrap_or(0);
+		if qlen > 0 {
+			ret.push(format!("{} blocks in queue", qlen));
 		}
+
+		let elen = self.manager.resync.errors_len().unwrap_or(0);
+		if elen > 0 {
+			ret.push(format!("{} blocks in error state", elen));
+		}
+
+		Some(ret.join(", "))
 	}

 	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
-		let (n_workers, tranquility) = self.persister.get_with(|x| (x.n_workers, x.tranquility));
-
-		if self.index >= n_workers {
+		if self.index >= self.manager.resync.persisted.load().n_workers {
 			return Ok(WorkerState::Idle);
 		}

 		self.tranquilizer.reset();
 		match self.manager.resync.resync_iter(&self.manager).await {
-			Ok(ResyncIterResult::BusyDidSomething) => {
-				Ok(self.tranquilizer.tranquilize_worker(tranquility))
-			}
+			Ok(ResyncIterResult::BusyDidSomething) => Ok(self
+				.tranquilizer
+				.tranquilize_worker(self.manager.resync.persisted.load().tranquility)),
 			Ok(ResyncIterResult::BusyDidNothing) => Ok(WorkerState::Busy),
 			Ok(ResyncIterResult::IdleFor(delay)) => {
 				self.next_delay = delay;
@ -549,8 +527,8 @@ impl Worker for ResyncWorker {
 		}
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
-		while self.index >= self.persister.get_with(|x| x.n_workers) {
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
+		while self.index >= self.manager.resync.persisted.load().n_workers {
 			self.manager.resync.notify.notified().await
 		}

@ -567,9 +545,9 @@ impl Worker for ResyncWorker {
 /// and the time of the last try.
 /// Used to implement exponential backoff.
 #[derive(Clone, Copy, Debug)]
-pub(crate) struct ErrorCounter {
-	pub(crate) errors: u64,
-	pub(crate) last_try: u64,
+struct ErrorCounter {
+	errors: u64,
+	last_try: u64,
 }

 impl ErrorCounter {
@ -580,13 +558,12 @@ impl ErrorCounter {
 		}
 	}

-	pub(crate) fn decode(data: &[u8]) -> Self {
+	fn decode(data: &[u8]) -> Self {
 		Self {
 			errors: u64::from_be_bytes(data[0..8].try_into().unwrap()),
 			last_try: u64::from_be_bytes(data[8..16].try_into().unwrap()),
 		}
 	}
-
 	fn encode(&self) -> Vec<u8> {
 		[
 			u64::to_be_bytes(self.errors),
@ -606,8 +583,7 @@ impl ErrorCounter {
 		(RESYNC_RETRY_DELAY.as_millis() as u64)
 			<< std::cmp::min(self.errors - 1, RESYNC_RETRY_DELAY_MAX_BACKOFF_POWER)
 	}
-
-	pub(crate) fn next_try(&self) -> u64 {
+	fn next_try(&self) -> u64 {
 		self.last_try + self.delay_msec()
 	}
 }
--- a/src/db/Cargo.toml
+++ b/src/db/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_db"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
--- a/src/db/lib.rs
+++ b/src/db/lib.rs
@ -181,10 +181,6 @@ impl Tree {
 	pub fn len(&self) -> Result<usize> {
 		self.0.len(self.1)
 	}
-	#[inline]
-	pub fn fast_len(&self) -> Result<Option<usize>> {
-		self.0.fast_len(self.1)
-	}

 	#[inline]
 	pub fn first(&self) -> Result<Option<(Value, Value)>> {
@ -327,9 +323,6 @@ pub(crate) trait IDb: Send + Sync {

 	fn get(&self, tree: usize, key: &[u8]) -> Result<Option<Value>>;
 	fn len(&self, tree: usize) -> Result<usize>;
-	fn fast_len(&self, _tree: usize) -> Result<Option<usize>> {
-		Ok(None)
-	}

 	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<Option<Value>>;
 	fn remove(&self, tree: usize, key: &[u8]) -> Result<Option<Value>>;
--- a/src/db/lmdb_adapter.rs
+++ b/src/db/lmdb_adapter.rs
@ -121,10 +121,6 @@ impl IDb for LmdbDb {
 		Ok(tree.len(&tx)?.try_into().unwrap())
 	}

-	fn fast_len(&self, tree: usize) -> Result<Option<usize>> {
-		Ok(Some(self.len(tree)?))
-	}
-
 	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<Option<Value>> {
 		let tree = self.get_tree(tree)?;
 		let mut tx = self.db.write_txn()?;
--- a/src/db/sqlite_adapter.rs
+++ b/src/db/sqlite_adapter.rs
@ -144,10 +144,6 @@ impl IDb for SqliteDb {
 		}
 	}

-	fn fast_len(&self, tree: usize) -> Result<Option<usize>> {
-		Ok(Some(self.len(tree)?))
-	}
-
 	fn insert(&self, tree: usize, key: &[u8], value: &[u8]) -> Result<Option<Value>> {
 		trace!("insert {}: lock db", tree);
 		let this = self.0.lock().unwrap();
--- a/src/garage/Cargo.toml
+++ b/src/garage/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -21,14 +21,14 @@ path = "tests/lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_db = { version = "0.8.1", path = "../db" }
-garage_api = { version = "0.8.1", path = "../api" }
-garage_block = { version = "0.8.1", path = "../block" }
-garage_model = { version = "0.8.1", path = "../model" }
-garage_rpc = { version = "0.8.1", path = "../rpc" }
-garage_table = { version = "0.8.1", path = "../table" }
-garage_util = { version = "0.8.1", path = "../util" }
-garage_web = { version = "0.8.1", path = "../web" }
+garage_db = { version = "0.8.0", path = "../db" }
+garage_api = { version = "0.8.0", path = "../api" }
+garage_block = { version = "0.8.0", path = "../block" }
+garage_model = { version = "0.8.0", path = "../model" }
+garage_rpc = { version = "0.8.0", path = "../rpc" }
+garage_table = { version = "0.8.0", path = "../table" }
+garage_util = { version = "0.8.0", path = "../util" }
+garage_web = { version = "0.8.0", path = "../web" }

 backtrace = "0.3"
 bytes = "1.0"
@ -42,6 +42,7 @@ rand = "0.8"
 async-trait = "0.1.7"
 sodiumoxide = { version = "0.2.5-0", package = "kuska-sodiumoxide" }

+rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"
 structopt = { version = "0.3", default-features = false }
@ -73,7 +74,7 @@ base64 = "0.13"


 [features]
-default = [ "bundled-libs", "metrics", "sled", "k2v" ]
+default = [ "bundled-libs", "metrics", "sled" ]

 k2v = [ "garage_util/k2v", "garage_api/k2v" ]

--- a/src/garage/admin.rs
+++ b/src/garage/admin.rs
@ -5,11 +5,9 @@ use std::sync::Arc;
 use async_trait::async_trait;
 use serde::{Deserialize, Serialize};

-use garage_util::background::BackgroundRunner;
 use garage_util::crdt::*;
 use garage_util::data::*;
 use garage_util::error::Error as GarageError;
-use garage_util::formater::format_table_to_string;
 use garage_util::time::*;

 use garage_table::replication::*;
@ -17,7 +15,7 @@ use garage_table::*;

 use garage_rpc::*;

-use garage_block::manager::BlockResyncErrorInfo;
+use garage_block::repair::ScrubWorkerCommand;

 use garage_model::bucket_alias_table::*;
 use garage_model::bucket_table::*;
@ -26,8 +24,6 @@ use garage_model::helper::error::{Error, OkOrBadRequest};
 use garage_model::key_table::*;
 use garage_model::migrate::Migrate;
 use garage_model::permission::*;
-use garage_model::s3::object_table::*;
-use garage_model::s3::version_table::Version;

 use crate::cli::*;
 use crate::repair::online::launch_online_repair;
@ -42,8 +38,7 @@ pub enum AdminRpc {
 	LaunchRepair(RepairOpt),
 	Migrate(MigrateOpt),
 	Stats(StatsOpt),
-	Worker(WorkerOperation),
-	BlockOperation(BlockOperation),
+	Worker(WorkerOpt),

 	// Replies
 	Ok(String),
@ -59,14 +54,6 @@ pub enum AdminRpc {
 		HashMap<usize, garage_util::background::WorkerInfo>,
 		WorkerListOpt,
 	),
-	WorkerVars(Vec<(Uuid, String, String)>),
-	WorkerInfo(usize, garage_util::background::WorkerInfo),
-	BlockErrorList(Vec<BlockResyncErrorInfo>),
-	BlockInfo {
-		hash: Hash,
-		refcount: u64,
-		versions: Vec<Result<Version, Uuid>>,
-	},
 }

 impl Rpc for AdminRpc {
@ -75,24 +62,17 @@ impl Rpc for AdminRpc {

 pub struct AdminRpcHandler {
 	garage: Arc<Garage>,
-	background: Arc<BackgroundRunner>,
 	endpoint: Arc<Endpoint<AdminRpc, Self>>,
 }

 impl AdminRpcHandler {
-	pub fn new(garage: Arc<Garage>, background: Arc<BackgroundRunner>) -> Arc<Self> {
+	pub fn new(garage: Arc<Garage>) -> Arc<Self> {
 		let endpoint = garage.system.netapp.endpoint(ADMIN_RPC_PATH.into());
-		let admin = Arc::new(Self {
-			garage,
-			background,
-			endpoint,
-		});
+		let admin = Arc::new(Self { garage, endpoint });
 		admin.endpoint.set_handler(admin.clone());
 		admin
 	}

-	// ================ BUCKET COMMANDS ====================
-
 	async fn handle_bucket_cmd(&self, cmd: &BucketOperation) -> Result<AdminRpc, Error> {
 		match cmd {
 			BucketOperation::List => self.handle_list_buckets().await,
@ -571,8 +551,6 @@ impl AdminRpcHandler {
 		Ok(AdminRpc::Ok(ret))
 	}

-	// ================ KEY COMMANDS ====================
-
 	async fn handle_key_cmd(&self, cmd: &KeyOperation) -> Result<AdminRpc, Error> {
 		match cmd {
 			KeyOperation::List => self.handle_list_keys().await,
@ -710,8 +688,6 @@ impl AdminRpcHandler {
 		Ok(AdminRpc::KeyInfo(key, relevant_buckets))
 	}

-	// ================ MIGRATION COMMANDS ====================
-
 	async fn handle_migrate(self: &Arc<Self>, opt: MigrateOpt) -> Result<AdminRpc, Error> {
 		if !opt.yes {
 			return Err(Error::BadRequest(
@ -728,8 +704,6 @@ impl AdminRpcHandler {
 		Ok(AdminRpc::Ok("Migration successfull.".into()))
 	}

-	// ================ REPAIR COMMANDS ====================
-
 	async fn handle_launch_repair(self: &Arc<Self>, opt: RepairOpt) -> Result<AdminRpc, Error> {
 		if !opt.yes {
 			return Err(Error::BadRequest(
@ -765,7 +739,7 @@ impl AdminRpcHandler {
 				)))
 			}
 		} else {
-			launch_online_repair(&self.garage, &self.background, opt).await?;
+			launch_online_repair(self.garage.clone(), opt).await;
 			Ok(AdminRpc::Ok(format!(
 				"Repair launched on {:?}",
 				self.garage.system.id
@ -773,8 +747,6 @@ impl AdminRpcHandler {
 		}
 	}

-	// ================ STATS COMMANDS ====================
-
 	async fn handle_stats(&self, opt: StatsOpt) -> Result<AdminRpc, Error> {
 		if opt.all_nodes {
 			let mut ret = String::new();
@ -791,12 +763,11 @@ impl AdminRpcHandler {
 				match self
 					.endpoint
 					.call(&node_id, AdminRpc::Stats(opt), PRIO_NORMAL)
-					.await
+					.await?
 				{
-					Ok(Ok(AdminRpc::Ok(s))) => writeln!(&mut ret, "{}", s).unwrap(),
-					Ok(Ok(x)) => writeln!(&mut ret, "Bad answer: {:?}", x).unwrap(),
-					Ok(Err(e)) => writeln!(&mut ret, "Remote error: {}", e).unwrap(),
-					Err(e) => writeln!(&mut ret, "Network error: {}", e).unwrap(),
+					Ok(AdminRpc::Ok(s)) => writeln!(&mut ret, "{}", s).unwrap(),
+					Ok(x) => writeln!(&mut ret, "Bad answer: {:?}", x).unwrap(),
+					Err(e) => writeln!(&mut ret, "Error: {}", e).unwrap(),
 				}
 			}
 			Ok(AdminRpc::Ok(ret))
@ -816,7 +787,6 @@ impl AdminRpcHandler {
 				.unwrap_or_else(|| "(unknown)".into()),
 		)
 		.unwrap();
-
 		writeln!(&mut ret, "\nDatabase engine: {}", self.garage.db.engine()).unwrap();

 		// Gather ring statistics
@ -835,38 +805,21 @@ impl AdminRpcHandler {
 			writeln!(&mut ret, "  {:?} {}", n, c).unwrap();
 		}

-		// Gather table statistics
-		let mut table = vec!["  Table\tItems\tMklItems\tMklTodo\tGcTodo".into()];
-		table.push(self.gather_table_stats(&self.garage.bucket_table, opt.detailed)?);
-		table.push(self.gather_table_stats(&self.garage.key_table, opt.detailed)?);
-		table.push(self.gather_table_stats(&self.garage.object_table, opt.detailed)?);
-		table.push(self.gather_table_stats(&self.garage.version_table, opt.detailed)?);
-		table.push(self.gather_table_stats(&self.garage.block_ref_table, opt.detailed)?);
-		write!(
-			&mut ret,
-			"\nTable stats:\n{}",
-			format_table_to_string(table)
-		)
-		.unwrap();
+		self.gather_table_stats(&mut ret, &self.garage.bucket_table, &opt)?;
+		self.gather_table_stats(&mut ret, &self.garage.key_table, &opt)?;
+		self.gather_table_stats(&mut ret, &self.garage.object_table, &opt)?;
+		self.gather_table_stats(&mut ret, &self.garage.version_table, &opt)?;
+		self.gather_table_stats(&mut ret, &self.garage.block_ref_table, &opt)?;

-		// Gather block manager statistics
 		writeln!(&mut ret, "\nBlock manager stats:").unwrap();
-		let rc_len = if opt.detailed {
-			self.garage.block_manager.rc_len()?.to_string()
-		} else {
-			self.garage
-				.block_manager
-				.rc_fast_len()?
-				.map(|x| x.to_string())
-				.unwrap_or_else(|| "NC".into())
-		};
-
+		if opt.detailed {
 			writeln!(
 				&mut ret,
 				"  number of RC entries (~= number of blocks): {}",
-			rc_len
+				self.garage.block_manager.rc_len()?
 			)
 			.unwrap();
+		}
 		writeln!(
 			&mut ret,
 			"  resync queue length: {}",
@ -880,305 +833,79 @@ impl AdminRpcHandler {
 		)
 		.unwrap();

-		if !opt.detailed {
-			writeln!(&mut ret, "\nIf values are missing (marked as NC), consider adding the --detailed flag - this will be slow.").unwrap();
-		}
-
 		Ok(ret)
 	}

 	fn gather_table_stats<F, R>(
 		&self,
+		to: &mut String,
 		t: &Arc<Table<F, R>>,
-		detailed: bool,
-	) -> Result<String, Error>
+		opt: &StatsOpt,
+	) -> Result<(), Error>
 	where
 		F: TableSchema + 'static,
 		R: TableReplication + 'static,
 	{
-		let (data_len, mkl_len) = if detailed {
-			(
-				t.data.store.len().map_err(GarageError::from)?.to_string(),
-				t.merkle_updater.merkle_tree_len()?.to_string(),
+		writeln!(to, "\nTable stats for {}", F::TABLE_NAME).unwrap();
+		if opt.detailed {
+			writeln!(
+				to,
+				"  number of items: {}",
+				t.data.store.len().map_err(GarageError::from)?
 			)
-		} else {
-			(
-				t.data
-					.store
-					.fast_len()
-					.map_err(GarageError::from)?
-					.map(|x| x.to_string())
-					.unwrap_or_else(|| "NC".into()),
-				t.merkle_updater
-					.merkle_tree_fast_len()?
-					.map(|x| x.to_string())
-					.unwrap_or_else(|| "NC".into()),
+			.unwrap();
+			writeln!(
+				to,
+				"  Merkle tree size: {}",
+				t.merkle_updater.merkle_tree_len()?
 			)
-		};
-
-		Ok(format!(
-			"  {}\t{}\t{}\t{}\t{}",
-			F::TABLE_NAME,
-			data_len,
-			mkl_len,
-			t.merkle_updater.todo_len()?,
-			t.data.gc_todo_len()?
-		))
+			.unwrap();
 		}
-
-	// ================ WORKER COMMANDS ====================
-
-	async fn handle_worker_cmd(&self, cmd: &WorkerOperation) -> Result<AdminRpc, Error> {
-		match cmd {
-			WorkerOperation::List { opt } => {
-				let workers = self.background.get_worker_info();
-				Ok(AdminRpc::WorkerList(workers, *opt))
-			}
-			WorkerOperation::Info { tid } => {
-				let info = self
-					.background
-					.get_worker_info()
-					.get(tid)
-					.ok_or_bad_request(format!("No worker with TID {}", tid))?
-					.clone();
-				Ok(AdminRpc::WorkerInfo(*tid, info))
-			}
-			WorkerOperation::Get {
-				all_nodes,
-				variable,
-			} => self.handle_get_var(*all_nodes, variable).await,
-			WorkerOperation::Set {
-				all_nodes,
-				variable,
-				value,
-			} => self.handle_set_var(*all_nodes, variable, value).await,
-		}
-	}
-
-	async fn handle_get_var(
-		&self,
-		all_nodes: bool,
-		variable: &Option<String>,
-	) -> Result<AdminRpc, Error> {
-		if all_nodes {
-			let mut ret = vec![];
-			let ring = self.garage.system.ring.borrow().clone();
-			for node in ring.layout.node_ids().iter() {
-				let node = (*node).into();
-				match self
-					.endpoint
-					.call(
-						&node,
-						AdminRpc::Worker(WorkerOperation::Get {
-							all_nodes: false,
-							variable: variable.clone(),
-						}),
-						PRIO_NORMAL,
+		writeln!(
+			to,
+			"  Merkle updater todo queue length: {}",
+			t.merkle_updater.todo_len()?
 		)
-					.await??
-				{
-					AdminRpc::WorkerVars(v) => ret.extend(v),
-					m => return Err(GarageError::unexpected_rpc_message(m).into()),
-				}
-			}
-			Ok(AdminRpc::WorkerVars(ret))
-		} else {
-			#[allow(clippy::collapsible_else_if)]
-			if let Some(v) = variable {
-				Ok(AdminRpc::WorkerVars(vec![(
-					self.garage.system.id,
-					v.clone(),
-					self.garage.bg_vars.get(v)?,
-				)]))
-			} else {
-				let mut vars = self.garage.bg_vars.get_all();
-				vars.sort();
-				Ok(AdminRpc::WorkerVars(
-					vars.into_iter()
-						.map(|(k, v)| (self.garage.system.id, k.to_string(), v))
-						.collect(),
-				))
-			}
-		}
+		.unwrap();
+		writeln!(to, "  GC todo queue length: {}", t.data.gc_todo_len()?).unwrap();
+
+		Ok(())
 	}

-	async fn handle_set_var(
-		&self,
-		all_nodes: bool,
-		variable: &str,
-		value: &str,
-	) -> Result<AdminRpc, Error> {
-		if all_nodes {
-			let mut ret = vec![];
-			let ring = self.garage.system.ring.borrow().clone();
-			for node in ring.layout.node_ids().iter() {
-				let node = (*node).into();
-				match self
-					.endpoint
-					.call(
-						&node,
-						AdminRpc::Worker(WorkerOperation::Set {
-							all_nodes: false,
-							variable: variable.to_string(),
-							value: value.to_string(),
-						}),
-						PRIO_NORMAL,
-					)
-					.await??
-				{
-					AdminRpc::WorkerVars(v) => ret.extend(v),
-					m => return Err(GarageError::unexpected_rpc_message(m).into()),
-				}
-			}
-			Ok(AdminRpc::WorkerVars(ret))
-		} else {
-			self.garage.bg_vars.set(variable, value)?;
-			Ok(AdminRpc::WorkerVars(vec![(
-				self.garage.system.id,
-				variable.to_string(),
-				value.to_string(),
-			)]))
-		}
-	}
+	// ----

-	// ================ BLOCK COMMANDS ====================
-
-	async fn handle_block_cmd(&self, cmd: &BlockOperation) -> Result<AdminRpc, Error> {
-		match cmd {
-			BlockOperation::ListErrors => Ok(AdminRpc::BlockErrorList(
-				self.garage.block_manager.list_resync_errors()?,
-			)),
-			BlockOperation::Info { hash } => {
-				let hash = hex::decode(hash).ok_or_bad_request("invalid hash")?;
-				let hash = Hash::try_from(&hash).ok_or_bad_request("invalid hash")?;
-				let refcount = self.garage.block_manager.get_block_rc(&hash)?;
-				let block_refs = self
-					.garage
-					.block_ref_table
-					.get_range(&hash, None, None, 10000, Default::default())
+	async fn handle_worker_cmd(&self, opt: WorkerOpt) -> Result<AdminRpc, Error> {
+		match opt.cmd {
+			WorkerCmd::List { opt } => {
+				let workers = self.garage.background.get_worker_info();
+				Ok(AdminRpc::WorkerList(workers, opt))
+			}
+			WorkerCmd::Set { opt } => match opt {
+				WorkerSetCmd::ScrubTranquility { tranquility } => {
+					let scrub_command = ScrubWorkerCommand::SetTranquility(tranquility);
+					self.garage
+						.block_manager
+						.send_scrub_command(scrub_command)
+						.await;
+					Ok(AdminRpc::Ok("Scrub tranquility updated".into()))
+				}
+				WorkerSetCmd::ResyncNWorkers { n_workers } => {
+					self.garage
+						.block_manager
+						.resync
+						.set_n_workers(n_workers)
 						.await?;
-				let mut versions = vec![];
-				for br in block_refs {
-					if let Some(v) = self
-						.garage
-						.version_table
-						.get(&br.version, &EmptyKey)
-						.await?
-					{
-						versions.push(Ok(v));
-					} else {
-						versions.push(Err(br.version));
+					Ok(AdminRpc::Ok("Number of resync workers updated".into()))
 				}
-				}
-				Ok(AdminRpc::BlockInfo {
-					hash,
-					refcount,
-					versions,
-				})
-			}
-			BlockOperation::RetryNow { all, blocks } => {
-				if *all {
-					if !blocks.is_empty() {
-						return Err(Error::BadRequest(
-							"--all was specified, cannot also specify blocks".into(),
-						));
-					}
-					let blocks = self.garage.block_manager.list_resync_errors()?;
-					for b in blocks.iter() {
-						self.garage.block_manager.resync.clear_backoff(&b.hash)?;
-					}
-					Ok(AdminRpc::Ok(format!(
-						"{} blocks returned in queue for a retry now (check logs to see results)",
-						blocks.len()
-					)))
-				} else {
-					for hash in blocks {
-						let hash = hex::decode(hash).ok_or_bad_request("invalid hash")?;
-						let hash = Hash::try_from(&hash).ok_or_bad_request("invalid hash")?;
-						self.garage.block_manager.resync.clear_backoff(&hash)?;
-					}
-					Ok(AdminRpc::Ok(format!(
-						"{} blocks returned in queue for a retry now (check logs to see results)",
-						blocks.len()
-					)))
-				}
-			}
-			BlockOperation::Purge { yes, blocks } => {
-				if !yes {
-					return Err(Error::BadRequest(
-						"Pass the --yes flag to confirm block purge operation.".into(),
-					));
-				}
-
-				let mut obj_dels = 0;
-				let mut ver_dels = 0;
-
-				for hash in blocks {
-					let hash = hex::decode(hash).ok_or_bad_request("invalid hash")?;
-					let hash = Hash::try_from(&hash).ok_or_bad_request("invalid hash")?;
-					let block_refs = self
-						.garage
-						.block_ref_table
-						.get_range(&hash, None, None, 10000, Default::default())
+				WorkerSetCmd::ResyncTranquility { tranquility } => {
+					self.garage
+						.block_manager
+						.resync
+						.set_tranquility(tranquility)
 						.await?;
-
-					for br in block_refs {
-						let version = match self
-							.garage
-							.version_table
-							.get(&br.version, &EmptyKey)
-							.await?
-						{
-							Some(v) => v,
-							None => continue,
-						};
-
-						if let Some(object) = self
-							.garage
-							.object_table
-							.get(&version.bucket_id, &version.key)
-							.await?
-						{
-							let ov = object.versions().iter().rev().find(|v| v.is_complete());
-							if let Some(ov) = ov {
-								if ov.uuid == br.version {
-									let del_uuid = gen_uuid();
-									let deleted_object = Object::new(
-										version.bucket_id,
-										version.key.clone(),
-										vec![ObjectVersion {
-											uuid: del_uuid,
-											timestamp: ov.timestamp + 1,
-											state: ObjectVersionState::Complete(
-												ObjectVersionData::DeleteMarker,
-											),
-										}],
-									);
-									self.garage.object_table.insert(&deleted_object).await?;
-									obj_dels += 1;
-								}
-							}
-						}
-
-						if !version.deleted.get() {
-							let deleted_version = Version::new(
-								version.uuid,
-								version.bucket_id,
-								version.key.clone(),
-								true,
-							);
-							self.garage.version_table.insert(&deleted_version).await?;
-							ver_dels += 1;
-						}
-					}
-				}
-				Ok(AdminRpc::Ok(format!(
-					"{} blocks were purged: {} object deletion markers added, {} versions marked deleted",
-					blocks.len(),
-					obj_dels,
-					ver_dels
-				)))
+					Ok(AdminRpc::Ok("Resync tranquility updated".into()))
 				}
+			},
 		}
 	}
 }
@ -1196,8 +923,7 @@ impl EndpointHandler<AdminRpc> for AdminRpcHandler {
 			AdminRpc::Migrate(opt) => self.handle_migrate(opt.clone()).await,
 			AdminRpc::LaunchRepair(opt) => self.handle_launch_repair(opt.clone()).await,
 			AdminRpc::Stats(opt) => self.handle_stats(opt.clone()).await,
-			AdminRpc::Worker(wo) => self.handle_worker_cmd(wo).await,
-			AdminRpc::BlockOperation(bo) => self.handle_block_cmd(bo).await,
+			AdminRpc::Worker(opt) => self.handle_worker_cmd(opt.clone()).await,
 			m => Err(GarageError::unexpected_rpc_message(m).into()),
 		}
 	}
--- a/src/garage/cli/cmd.rs
+++ b/src/garage/cli/cmd.rs
@ -41,9 +41,6 @@ pub async fn cli_command_dispatch(
 		}
 		Command::Stats(so) => cmd_admin(admin_rpc_endpoint, rpc_host, AdminRpc::Stats(so)).await,
 		Command::Worker(wo) => cmd_admin(admin_rpc_endpoint, rpc_host, AdminRpc::Worker(wo)).await,
-		Command::Block(bo) => {
-			cmd_admin(admin_rpc_endpoint, rpc_host, AdminRpc::BlockOperation(bo)).await
-		}
 		_ => unreachable!(),
 	}
 }
@ -189,23 +186,7 @@ pub async fn cmd_admin(
 			print_key_info(&key, &rb);
 		}
 		AdminRpc::WorkerList(wi, wlo) => {
-			print_worker_list(wi, wlo);
-		}
-		AdminRpc::WorkerVars(wv) => {
-			print_worker_vars(wv);
-		}
-		AdminRpc::WorkerInfo(tid, wi) => {
-			print_worker_info(tid, wi);
-		}
-		AdminRpc::BlockErrorList(el) => {
-			print_block_error_list(el);
-		}
-		AdminRpc::BlockInfo {
-			hash,
-			refcount,
-			versions,
-		} => {
-			print_block_info(hash, refcount, versions);
+			print_worker_info(wi, wlo);
 		}
 		r => {
 			error!("Unexpected response: {:?}", r);
--- a/src/garage/cli/structs.rs
+++ b/src/garage/cli/structs.rs
@ -49,11 +49,7 @@ pub enum Command {

 	/// Manage background workers
 	#[structopt(name = "worker", version = garage_version())]
-	Worker(WorkerOperation),
-
-	/// Low-level debug operations on data blocks
-	#[structopt(name = "block", version = garage_version())]
-	Block(BlockOperation),
+	Worker(WorkerOpt),
 }

 #[derive(StructOpt, Debug)]
@ -506,36 +502,25 @@ pub struct StatsOpt {
 	pub detailed: bool,
 }

+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
+pub struct WorkerOpt {
+	#[structopt(subcommand)]
+	pub cmd: WorkerCmd,
+}
+
 #[derive(Serialize, Deserialize, StructOpt, Debug, Eq, PartialEq, Clone)]
-pub enum WorkerOperation {
+pub enum WorkerCmd {
 	/// List all workers on Garage node
 	#[structopt(name = "list", version = garage_version())]
 	List {
 		#[structopt(flatten)]
 		opt: WorkerListOpt,
 	},
-	/// Get detailed information about a worker
-	#[structopt(name = "info", version = garage_version())]
-	Info { tid: usize },
-	/// Get worker parameter
-	#[structopt(name = "get", version = garage_version())]
-	Get {
-		/// Gather variable values from all nodes
-		#[structopt(short = "a", long = "all-nodes")]
-		all_nodes: bool,
-		/// Variable name to get, or none to get all variables
-		variable: Option<String>,
-	},
 	/// Set worker parameter
 	#[structopt(name = "set", version = garage_version())]
 	Set {
-		/// Set variable values on all nodes
-		#[structopt(short = "a", long = "all-nodes")]
-		all_nodes: bool,
-		/// Variable node to set
-		variable: String,
-		/// Value to set the variable to
-		value: String,
+		#[structopt(subcommand)]
+		opt: WorkerSetCmd,
 	},
 }

@ -550,33 +535,14 @@ pub struct WorkerListOpt {
 }

 #[derive(Serialize, Deserialize, StructOpt, Debug, Eq, PartialEq, Clone)]
-pub enum BlockOperation {
-	/// List all blocks that currently have a resync error
-	#[structopt(name = "list-errors", version = garage_version())]
-	ListErrors,
-	/// Get detailed information about a single block
-	#[structopt(name = "info", version = garage_version())]
-	Info {
-		/// Hash of the block for which to retrieve information
-		hash: String,
-	},
-	/// Retry now the resync of one or many blocks
-	#[structopt(name = "retry-now", version = garage_version())]
-	RetryNow {
-		/// Retry all blocks that have a resync error
-		#[structopt(long = "all")]
-		all: bool,
-		/// Hashes of the block to retry to resync now
-		blocks: Vec<String>,
-	},
-	/// Delete all objects referencing a missing block
-	#[structopt(name = "purge", version = garage_version())]
-	Purge {
-		/// Mandatory to confirm this operation
-		#[structopt(long = "yes")]
-		yes: bool,
-		/// Hashes of the block to purge
-		#[structopt(required = true)]
-		blocks: Vec<String>,
-	},
+pub enum WorkerSetCmd {
+	/// Set tranquility of scrub operations
+	#[structopt(name = "scrub-tranquility", version = garage_version())]
+	ScrubTranquility { tranquility: u32 },
+	/// Set number of concurrent block resync workers
+	#[structopt(name = "resync-n-workers", version = garage_version())]
+	ResyncNWorkers { n_workers: usize },
+	/// Set tranquility of block resync operations
+	#[structopt(name = "resync-tranquility", version = garage_version())]
+	ResyncTranquility { tranquility: u32 },
 }
--- a/src/garage/cli/util.rs
+++ b/src/garage/cli/util.rs
@ -3,17 +3,14 @@ use std::time::Duration;

 use garage_util::background::*;
 use garage_util::crdt::*;
-use garage_util::data::*;
+use garage_util::data::Uuid;
 use garage_util::error::*;
 use garage_util::formater::format_table;
 use garage_util::time::*;

-use garage_block::manager::BlockResyncErrorInfo;
-
 use garage_model::bucket_table::*;
 use garage_model::key_table::*;
 use garage_model::s3::object_table::{BYTES, OBJECTS, UNFINISHED_UPLOADS};
-use garage_model::s3::version_table::Version;

 use crate::cli::structs::WorkerListOpt;

@ -244,7 +241,7 @@ pub fn find_matching_node(
 	}
 }

-pub fn print_worker_list(wi: HashMap<usize, WorkerInfo>, wlo: WorkerListOpt) {
+pub fn print_worker_info(wi: HashMap<usize, WorkerInfo>, wlo: WorkerListOpt) {
 	let mut wi = wi.into_iter().collect::<Vec<_>>();
 	wi.sort_by_key(|(tid, info)| {
 		(
@ -257,7 +254,7 @@ pub fn print_worker_list(wi: HashMap<usize, WorkerInfo>, wlo: WorkerListOpt) {
 		)
 	});

-	let mut table = vec!["TID\tState\tName\tTranq\tDone\tQueue\tErrors\tConsec\tLast".to_string()];
+	let mut table = vec![];
 	for (tid, info) in wi.iter() {
 		if wlo.busy && !matches!(info.state, WorkerState::Busy | WorkerState::Throttled(_)) {
 			continue;
@ -266,155 +263,33 @@ pub fn print_worker_list(wi: HashMap<usize, WorkerInfo>, wlo: WorkerListOpt) {
 			continue;
 		}

+		table.push(format!("{}\t{}\t{}", tid, info.state, info.name));
+		if let Some(i) = &info.info {
+			table.push(format!("\t\t  {}", i));
+		}
 		let tf = timeago::Formatter::new();
-		let err_ago = info
+		let (err_ago, err_msg) = info
 			.last_error
 			.as_ref()
-			.map(|(_, t)| tf.convert(Duration::from_millis(now_msec() - t)))
-			.unwrap_or_default();
-		let (total_err, consec_err) = if info.errors > 0 {
-			(info.errors.to_string(), info.consecutive_errors.to_string())
-		} else {
-			("-".into(), "-".into())
-		};
-
+			.map(|(m, t)| {
+				(
+					tf.convert(Duration::from_millis(now_msec() - t)),
+					m.as_str(),
+				)
+			})
+			.unwrap_or(("(?) ago".into(), "(?)"));
+		if info.consecutive_errors > 0 {
 			table.push(format!(
-			"{}\t{}\t{}\t{}\t{}\t{}\t{}\t{}\t{}",
-			tid,
-			info.state,
-			info.name,
-			info.status
-				.tranquility
-				.as_ref()
-				.map(ToString::to_string)
-				.unwrap_or_else(|| "-".into()),
-			info.status.progress.as_deref().unwrap_or("-"),
-			info.status
-				.queue_length
-				.as_ref()
-				.map(ToString::to_string)
-				.unwrap_or_else(|| "-".into()),
-			total_err,
-			consec_err,
-			err_ago,
+				"\t\t  {} consecutive errors ({} total), last {}",
+				info.consecutive_errors, info.errors, err_ago,
 			));
+			table.push(format!("\t\t  {}", err_msg));
+		} else if info.errors > 0 {
+			table.push(format!("\t\t  ({} errors, last {})", info.errors, err_ago,));
+			if wlo.errors {
+				table.push(format!("\t\t  {}", err_msg));
 			}
-	format_table(table);
-}
-
-pub fn print_worker_info(tid: usize, info: WorkerInfo) {
-	let mut table = vec![];
-	table.push(format!("Task id:\t{}", tid));
-	table.push(format!("Worker name:\t{}", info.name));
-	match info.state {
-		WorkerState::Throttled(t) => {
-			table.push(format!(
-				"Worker state:\tBusy (throttled, paused for {:.3}s)",
-				t
-			));
-		}
-		s => {
-			table.push(format!("Worker state:\t{}", s));
-		}
-	};
-	if let Some(tql) = info.status.tranquility {
-		table.push(format!("Tranquility:\t{}", tql));
-	}
-
-	table.push("".into());
-	table.push(format!("Total errors:\t{}", info.errors));
-	table.push(format!("Consecutive errs:\t{}", info.consecutive_errors));
-	if let Some((s, t)) = info.last_error {
-		table.push(format!("Last error:\t{}", s));
-		let tf = timeago::Formatter::new();
-		table.push(format!(
-			"Last error time:\t{}",
-			tf.convert(Duration::from_millis(now_msec() - t))
-		));
-	}
-
-	table.push("".into());
-	if let Some(p) = info.status.progress {
-		table.push(format!("Progress:\t{}", p));
-	}
-	if let Some(ql) = info.status.queue_length {
-		table.push(format!("Queue length:\t{}", ql));
-	}
-	if let Some(pe) = info.status.persistent_errors {
-		table.push(format!("Persistent errors:\t{}", pe));
-	}
-
-	for (i, s) in info.status.freeform.iter().enumerate() {
-		if i == 0 {
-			if table.last() != Some(&"".into()) {
-				table.push("".into());
-			}
-			table.push(format!("Message:\t{}", s));
-		} else {
-			table.push(format!("\t{}", s));
 		}
 	}
 	format_table(table);
 }
-
-pub fn print_worker_vars(wv: Vec<(Uuid, String, String)>) {
-	let table = wv
-		.into_iter()
-		.map(|(n, k, v)| format!("{:?}\t{}\t{}", n, k, v))
-		.collect::<Vec<_>>();
-	format_table(table);
-}
-
-pub fn print_block_error_list(el: Vec<BlockResyncErrorInfo>) {
-	let now = now_msec();
-	let tf = timeago::Formatter::new();
-	let mut tf2 = timeago::Formatter::new();
-	tf2.ago("");
-
-	let mut table = vec!["Hash\tRC\tErrors\tLast error\tNext try".into()];
-	for e in el {
-		table.push(format!(
-			"{}\t{}\t{}\t{}\tin {}",
-			hex::encode(e.hash.as_slice()),
-			e.refcount,
-			e.error_count,
-			tf.convert(Duration::from_millis(now - e.last_try)),
-			tf2.convert(Duration::from_millis(e.next_try - now))
-		));
-	}
-	format_table(table);
-}
-
-pub fn print_block_info(hash: Hash, refcount: u64, versions: Vec<Result<Version, Uuid>>) {
-	println!("Block hash: {}", hex::encode(hash.as_slice()));
-	println!("Refcount: {}", refcount);
-	println!();
-
-	let mut table = vec!["Version\tBucket\tKey\tDeleted".into()];
-	let mut nondeleted_count = 0;
-	for v in versions.iter() {
-		match v {
-			Ok(ver) => {
-				table.push(format!(
-					"{:?}\t{:?}\t{}\t{:?}",
-					ver.uuid,
-					ver.bucket_id,
-					ver.key,
-					ver.deleted.get()
-				));
-				if !ver.deleted.get() {
-					nondeleted_count += 1;
-				}
-			}
-			Err(vh) => {
-				table.push(format!("{:?}\t\t\tyes", vh));
-			}
-		}
-	}
-	format_table(table);
-
-	if refcount != nondeleted_count {
-		println!();
-		println!("Warning: refcount does not match number of non-deleted versions");
-	}
-}
--- a/src/garage/main.rs
+++ b/src/garage/main.rs
@ -127,16 +127,9 @@ async fn main() {
 		std::process::abort();
 	}));

-	// Parse arguments and dispatch command line
-	let opt = Opt::from_clap(&Opt::clap().version(version.as_str()).get_matches());
-
 	// Initialize logging as well as other libraries used in Garage
 	if std::env::var("RUST_LOG").is_err() {
-		let default_log = match &opt.cmd {
-			Command::Server => "netapp=info,garage=info",
-			_ => "netapp=warn,garage=warn",
-		};
-		std::env::set_var("RUST_LOG", default_log)
+		std::env::set_var("RUST_LOG", "netapp=info,garage=info")
 	}
 	tracing_subscriber::fmt()
 		.with_writer(std::io::stderr)
@ -144,6 +137,9 @@ async fn main() {
 		.init();
 	sodiumoxide::init().expect("Unable to init sodiumoxide");

+	// Parse arguments and dispatch command line
+	let opt = Opt::from_clap(&Opt::clap().version(version.as_str()).get_matches());
+
 	let res = match opt.cmd {
 		Command::Server => server::run_server(opt.config_file).await,
 		Command::OfflineRepair(repair_opt) => {
@ -173,7 +169,7 @@ async fn cli_command(opt: Opt) -> Result<(), Error> {
 	let net_key_hex_str = opt
 		.rpc_secret
 		.as_ref()
-		.or_else(|| config.as_ref().and_then(|c| c.rpc_secret.as_ref()))
+		.or_else(|| config.as_ref().map(|c| &c.rpc_secret))
 		.ok_or("No RPC secret provided")?;
 	let network_key = NetworkKey::from_slice(
 		&hex::decode(net_key_hex_str).err_context("Invalid RPC secret key (bad hex)")?[..],
@ -186,9 +182,9 @@ async fn cli_command(opt: Opt) -> Result<(), Error> {
 	let netapp = NetApp::new(GARAGE_VERSION_TAG, network_key, sk);

 	// Find and parse the address of the target host
-	let (id, addr, is_default_addr) = if let Some(h) = opt.rpc_host {
+	let (id, addr) = if let Some(h) = opt.rpc_host {
 		let (id, addrs) = parse_and_resolve_peer_addr(&h).ok_or_else(|| format!("Invalid RPC remote node identifier: {}. Expected format is <pubkey>@<IP or hostname>:<port>.", h))?;
-		(id, addrs[0], false)
+		(id, addrs[0])
 	} else {
 		let node_id = garage_rpc::system::read_node_id(&config.as_ref().unwrap().metadata_dir)
 			.err_context(READ_KEY_ERROR)?;
@ -199,26 +195,24 @@ async fn cli_command(opt: Opt) -> Result<(), Error> {
 				.ok_or_message("unable to resolve rpc_public_addr specified in config file")?
 				.next()
 				.ok_or_message("unable to resolve rpc_public_addr specified in config file")?;
-			(node_id, a, false)
+			(node_id, a)
 		} else {
 			let default_addr = SocketAddr::new(
 				"127.0.0.1".parse().unwrap(),
 				config.as_ref().unwrap().rpc_bind_addr.port(),
 			);
-			(node_id, default_addr, true)
+			warn!(
+				"Trying to contact Garage node at default address {}",
+				default_addr
+			);
+			warn!("If this doesn't work, consider adding rpc_public_addr in your config file or specifying the -h command line parameter.");
+			(node_id, default_addr)
 		}
 	};

 	// Connect to target host
-	if let Err(e) = netapp.clone().try_connect(addr, id).await {
-		if is_default_addr {
-			warn!(
-				"Tried to contact Garage node at default address {}, which didn't work. If that address is wrong, consider setting rpc_public_addr in your config file.",
-				addr
-			);
-		}
-		Err(e).err_context("Unable to connect to destination RPC host. Check that you are using the same value of rpc_secret as them, and that you have their correct public key.")?;
-	}
+	netapp.clone().try_connect(addr, id).await
+		.err_context("Unable to connect to destination RPC host. Check that you are using the same value of rpc_secret as them, and that you have their correct public key.")?;

 	let system_rpc_endpoint = netapp.endpoint::<SystemRpc, ()>(SYSTEM_RPC_PATH.into());
 	let admin_rpc_endpoint = netapp.endpoint::<AdminRpc, ()>(ADMIN_RPC_PATH.into());
--- a/src/garage/repair/offline.rs
+++ b/src/garage/repair/offline.rs
@ -1,5 +1,8 @@
 use std::path::PathBuf;

+use tokio::sync::watch;
+
+use garage_util::background::*;
 use garage_util::config::*;
 use garage_util::error::*;

@ -17,8 +20,12 @@ pub async fn offline_repair(config_file: PathBuf, opt: OfflineRepairOpt) -> Resu
 	info!("Loading configuration...");
 	let config = read_config(config_file)?;

+	info!("Initializing background runner...");
+	let (done_tx, done_rx) = watch::channel(false);
+	let (background, await_background_done) = BackgroundRunner::new(16, done_rx);
+
 	info!("Initializing Garage main data store...");
-	let garage = Garage::new(config)?;
+	let garage = Garage::new(config.clone(), background)?;

 	info!("Launching repair operation...");
 	match opt.what {
@ -36,7 +43,13 @@ pub async fn offline_repair(config_file: PathBuf, opt: OfflineRepairOpt) -> Resu
 		}
 	}

-	info!("Repair operation finished, shutting down...");
+	info!("Repair operation finished, shutting down Garage internals...");
+	done_tx.send(true).unwrap();
+	drop(garage);
+
+	await_background_done.await?;
+
+	info!("Cleaning up...");

 	Ok(())
 }
--- a/src/garage/repair/online.rs
+++ b/src/garage/repair/online.rs
@ -12,35 +12,36 @@ use garage_model::s3::version_table::*;
 use garage_table::*;
 use garage_util::background::*;
 use garage_util::error::Error;
-use garage_util::migrate::Migrate;

 use crate::*;

-pub async fn launch_online_repair(
-	garage: &Arc<Garage>,
-	bg: &BackgroundRunner,
-	opt: RepairOpt,
-) -> Result<(), Error> {
+pub async fn launch_online_repair(garage: Arc<Garage>, opt: RepairOpt) {
 	match opt.what {
 		RepairWhat::Tables => {
 			info!("Launching a full sync of tables");
-			garage.bucket_table.syncer.add_full_sync()?;
-			garage.object_table.syncer.add_full_sync()?;
-			garage.version_table.syncer.add_full_sync()?;
-			garage.block_ref_table.syncer.add_full_sync()?;
-			garage.key_table.syncer.add_full_sync()?;
+			garage.bucket_table.syncer.add_full_sync();
+			garage.object_table.syncer.add_full_sync();
+			garage.version_table.syncer.add_full_sync();
+			garage.block_ref_table.syncer.add_full_sync();
+			garage.key_table.syncer.add_full_sync();
 		}
 		RepairWhat::Versions => {
 			info!("Repairing the versions table");
-			bg.spawn_worker(RepairVersionsWorker::new(garage.clone()));
+			garage
+				.background
+				.spawn_worker(RepairVersionsWorker::new(garage.clone()));
 		}
 		RepairWhat::BlockRefs => {
 			info!("Repairing the block refs table");
-			bg.spawn_worker(RepairBlockrefsWorker::new(garage.clone()));
+			garage
+				.background
+				.spawn_worker(RepairBlockrefsWorker::new(garage.clone()));
 		}
 		RepairWhat::Blocks => {
 			info!("Repairing the stored blocks");
-			bg.spawn_worker(garage_block::repair::RepairWorker::new(
+			garage
+				.background
+				.spawn_worker(garage_block::repair::RepairWorker::new(
 					garage.block_manager.clone(),
 				));
 		}
@ -51,18 +52,13 @@ pub async fn launch_online_repair(
 				ScrubCmd::Resume => ScrubWorkerCommand::Resume,
 				ScrubCmd::Cancel => ScrubWorkerCommand::Cancel,
 				ScrubCmd::SetTranquility { tranquility } => {
-					garage
-						.block_manager
-						.scrub_persister
-						.set_with(|x| x.tranquility = tranquility)?;
-					return Ok(());
+					ScrubWorkerCommand::SetTranquility(tranquility)
 				}
 			};
 			info!("Sending command to scrub worker: {:?}", cmd);
-			garage.block_manager.send_scrub_command(cmd).await?;
+			garage.block_manager.send_scrub_command(cmd).await;
 		}
 	}
-	Ok(())
 }

 // ----
@ -89,23 +85,25 @@ impl Worker for RepairVersionsWorker {
 		"Version repair worker".into()
 	}

-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			progress: Some(self.counter.to_string()),
-			..Default::default()
-		}
+	fn info(&self) -> Option<String> {
+		Some(format!("{} items done", self.counter))
 	}

 	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
-		let (item_bytes, next_pos) = match self.garage.version_table.data.store.get_gt(&self.pos)? {
-			Some((k, v)) => (v, k),
+		let item_bytes = match self.garage.version_table.data.store.get_gt(&self.pos)? {
+			Some((k, v)) => {
+				self.pos = k;
+				v
+			}
 			None => {
 				info!("repair_versions: finished, done {}", self.counter);
 				return Ok(WorkerState::Done);
 			}
 		};

-		let version = Version::decode(&item_bytes).ok_or_message("Cannot decode Version")?;
+		self.counter += 1;
+
+		let version = rmp_serde::decode::from_read_ref::<_, Version>(&item_bytes)?;
 		if !version.deleted.get() {
 			let object = self
 				.garage
@ -133,13 +131,10 @@ impl Worker for RepairVersionsWorker {
 			}
 		}

-		self.counter += 1;
-		self.pos = next_pos;
-
 		Ok(WorkerState::Busy)
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
 		unreachable!()
 	}
 }
@ -168,24 +163,25 @@ impl Worker for RepairBlockrefsWorker {
 		"Block refs repair worker".into()
 	}

-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			progress: Some(self.counter.to_string()),
-			..Default::default()
-		}
+	fn info(&self) -> Option<String> {
+		Some(format!("{} items done", self.counter))
 	}

 	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
-		let (item_bytes, next_pos) =
-			match self.garage.block_ref_table.data.store.get_gt(&self.pos)? {
-				Some((k, v)) => (v, k),
+		let item_bytes = match self.garage.block_ref_table.data.store.get_gt(&self.pos)? {
+			Some((k, v)) => {
+				self.pos = k;
+				v
+			}
 			None => {
 				info!("repair_block_ref: finished, done {}", self.counter);
 				return Ok(WorkerState::Done);
 			}
 		};

-		let block_ref = BlockRef::decode(&item_bytes).ok_or_message("Cannot decode BlockRef")?;
+		self.counter += 1;
+
+		let block_ref = rmp_serde::decode::from_read_ref::<_, BlockRef>(&item_bytes)?;
 		if !block_ref.deleted.get() {
 			let version = self
 				.garage
@ -210,13 +206,10 @@ impl Worker for RepairBlockrefsWorker {
 			}
 		}

-		self.counter += 1;
-		self.pos = next_pos;
-
 		Ok(WorkerState::Busy)
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
 		unreachable!()
 	}
 }
--- a/src/garage/server.rs
+++ b/src/garage/server.rs
@ -35,15 +35,12 @@ pub async fn run_server(config_file: PathBuf) -> Result<(), Error> {
 	#[cfg(feature = "metrics")]
 	let metrics_exporter = opentelemetry_prometheus::exporter().init();

-	info!("Initializing Garage main data store...");
-	let garage = Garage::new(config.clone())?;
-
 	info!("Initializing background runner...");
 	let watch_cancel = watch_shutdown_signal();
-	let (background, await_background_done) = BackgroundRunner::new(watch_cancel.clone());
+	let (background, await_background_done) = BackgroundRunner::new(16, watch_cancel.clone());

-	info!("Spawning Garage workers...");
-	garage.spawn_workers(&background);
+	info!("Initializing Garage main data store...");
+	let garage = Garage::new(config.clone(), background)?;

 	if config.admin.trace_sink.is_some() {
 		info!("Initialize tracing...");
@ -66,7 +63,7 @@ pub async fn run_server(config_file: PathBuf) -> Result<(), Error> {
 	let run_system = tokio::spawn(garage.system.clone().run(watch_cancel.clone()));

 	info!("Create admin RPC handler...");
-	AdminRpcHandler::new(garage.clone(), background.clone());
+	AdminRpcHandler::new(garage.clone());

 	// ---- Launch public-facing API servers ----

--- a/src/k2v-client/Cargo.toml
+++ b/src/k2v-client/Cargo.toml
@ -22,7 +22,7 @@ tokio = "1.17.0"

 # cli deps
 clap = { version = "3.1.18", optional = true, features = ["derive", "env"] }
-garage_util = { version = "0.8.1", path = "../util", optional = true }
+garage_util = { version = "0.8.0", path = "../util", optional = true }


 [features]
--- a/src/model/Cargo.toml
+++ b/src/model/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_model"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,11 +14,11 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_db = { version = "0.8.1", default-features = false, path = "../db" }
-garage_rpc = { version = "0.8.1", path = "../rpc" }
-garage_table = { version = "0.8.1", path = "../table" }
-garage_block = { version = "0.8.1", path = "../block" }
-garage_util = { version = "0.8.1", path = "../util" }
+garage_db = { version = "0.8.0", default-features = false, path = "../db" }
+garage_rpc = { version = "0.8.0", path = "../rpc" }
+garage_table = { version = "0.8.0", path = "../table" }
+garage_block = { version = "0.8.0", path = "../block" }
+garage_util = { version = "0.8.0", path = "../util" }

 async-trait = "0.1.7"
 arc-swap = "1.0"
@ -30,6 +30,7 @@ tracing = "0.1.30"
 rand = "0.8"
 zstd = { version = "0.9", default-features = false }

+rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"

--- a/src/model/bucket_alias_table.rs
+++ b/src/model/bucket_alias_table.rs
@ -1,26 +1,18 @@
+use serde::{Deserialize, Serialize};
+
 use garage_util::data::*;

 use garage_table::crdt::*;
 use garage_table::*;

-mod v08 {
-	use garage_util::crdt;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-
 /// The bucket alias table holds the names given to buckets
 /// in the global namespace.
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
 pub struct BucketAlias {
-		pub(super) name: String,
+	name: String,
 	pub state: crdt::Lww<Option<Uuid>>,
 }

-	impl garage_util::migrate::InitialFormat for BucketAlias {}
-}
-
-pub use v08::*;
-
 impl BucketAlias {
 	pub fn new(name: String, ts: u64, bucket_id: Option<Uuid>) -> Option<Self> {
 		if !is_valid_bucket_name(&name) {
--- a/src/model/bucket_table.rs
+++ b/src/model/bucket_table.rs
@ -1,3 +1,5 @@
+use serde::{Deserialize, Serialize};
+
 use garage_table::crdt::*;
 use garage_table::*;
 use garage_util::data::*;
@ -5,12 +7,6 @@ use garage_util::time::*;

 use crate::permission::BucketKeyPerm;

-mod v08 {
-	use crate::permission::BucketKeyPerm;
-	use garage_util::crdt;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-
 /// A bucket is a collection of objects
 ///
 /// Its parameters are not directly accessible as:
@ -77,11 +73,6 @@ mod v08 {
 	pub max_objects: Option<u64>,
 }

-	impl garage_util::migrate::InitialFormat for Bucket {}
-}
-
-pub use v08::*;
-
 impl AutoCrdt for BucketQuotas {
 	const WARN_IF_DIFFERENT: bool = true;
 }
--- a/src/model/garage.rs
+++ b/src/model/garage.rs
@ -33,14 +33,14 @@ use crate::k2v::{item_table::*, poll::*, rpc::*};
 pub struct Garage {
 	/// The parsed configuration Garage is running
 	pub config: Config,
-	/// The set of background variables that can be viewed/modified at runtime
-	pub bg_vars: vars::BgVars,

 	/// The replication mode of this cluster
 	pub replication_mode: ReplicationMode,

 	/// The local database
 	pub db: db::Db,
+	/// A background job runner
+	pub background: Arc<BackgroundRunner>,
 	/// The membership manager
 	pub system: Arc<System>,
 	/// The block manager
@ -78,7 +78,7 @@ pub struct GarageK2V {

 impl Garage {
 	/// Create and run garage
-	pub fn new(config: Config) -> Result<Arc<Self>, Error> {
+	pub fn new(config: Config, background: Arc<BackgroundRunner>) -> Result<Arc<Self>, Error> {
 		// Create meta dir and data dir if they don't exist already
 		std::fs::create_dir_all(&config.metadata_dir)
 			.ok_or_message("Unable to create Garage metadata directory")?;
@ -159,7 +159,7 @@ impl Garage {
 		};

 		let network_key = NetworkKey::from_slice(
-			&hex::decode(&config.rpc_secret.as_ref().unwrap()).expect("Invalid RPC secret key")[..],
+			&hex::decode(&config.rpc_secret).expect("Invalid RPC secret key")[..],
 		)
 		.expect("Invalid RPC secret key");

@ -167,7 +167,7 @@ impl Garage {
 			.expect("Invalid replication_mode in config file.");

 		info!("Initialize membership management system...");
-		let system = System::new(network_key, replication_mode, &config)?;
+		let system = System::new(network_key, background.clone(), replication_mode, &config)?;

 		let data_rep_param = TableShardedReplication {
 			system: system.clone(),
@ -225,6 +225,7 @@ impl Garage {
 		info!("Initialize version_table...");
 		let version_table = Table::new(
 			VersionTable {
+				background: background.clone(),
 				block_ref_table: block_ref_table.clone(),
 			},
 			meta_rep_param.clone(),
@ -239,6 +240,7 @@ impl Garage {
 		#[allow(clippy::redundant_clone)]
 		let object_table = Table::new(
 			ObjectTable {
+				background: background.clone(),
 				version_table: version_table.clone(),
 				object_counter_table: object_counter_table.clone(),
 			},
@ -251,16 +253,12 @@ impl Garage {
 		#[cfg(feature = "k2v")]
 		let k2v = GarageK2V::new(system.clone(), &db, meta_rep_param);

-		// Initialize bg vars
-		let mut bg_vars = vars::BgVars::new();
-		block_manager.register_bg_vars(&mut bg_vars);
-
 		// -- done --
 		Ok(Arc::new(Self {
 			config,
-			bg_vars,
 			replication_mode,
 			db,
+			background,
 			system,
 			block_manager,
 			bucket_table,
@ -275,22 +273,6 @@ impl Garage {
 		}))
 	}

-	pub fn spawn_workers(&self, bg: &BackgroundRunner) {
-		self.block_manager.spawn_workers(bg);
-
-		self.bucket_table.spawn_workers(bg);
-		self.bucket_alias_table.spawn_workers(bg);
-		self.key_table.spawn_workers(bg);
-
-		self.object_table.spawn_workers(bg);
-		self.object_counter_table.spawn_workers(bg);
-		self.version_table.spawn_workers(bg);
-		self.block_ref_table.spawn_workers(bg);
-
-		#[cfg(feature = "k2v")]
-		self.k2v.spawn_workers(bg);
-	}
-
 	pub fn bucket_helper(&self) -> helper::bucket::BucketHelper {
 		helper::bucket::BucketHelper(self)
 	}
@ -325,9 +307,4 @@ impl GarageK2V {
 			rpc,
 		}
 	}
-
-	pub fn spawn_workers(&self, bg: &BackgroundRunner) {
-		self.item_table.spawn_workers(bg);
-		self.counter_table.spawn_workers(bg);
-	}
 }
--- a/src/model/index_counter.rs
+++ b/src/model/index_counter.rs
@ -1,18 +1,19 @@
 use core::ops::Bound;
-use std::collections::{BTreeMap, HashMap};
+use std::collections::{hash_map, BTreeMap, HashMap};
 use std::marker::PhantomData;
 use std::sync::Arc;

+use async_trait::async_trait;
 use serde::{Deserialize, Serialize};
+use tokio::sync::{mpsc, watch};

 use garage_db as db;

 use garage_rpc::ring::Ring;
 use garage_rpc::system::System;
-use garage_util::background::BackgroundRunner;
+use garage_util::background::*;
 use garage_util::data::*;
 use garage_util::error::*;
-use garage_util::migrate::Migrate;
 use garage_util::time::*;

 use garage_table::crdt::*;
@ -30,14 +31,6 @@ pub trait CountedItem: Clone + PartialEq + Send + Sync + 'static {
 	fn counts(&self) -> Vec<(&'static str, i64)>;
 }

-mod v08 {
-	use super::CountedItem;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-	use std::collections::BTreeMap;
-
-	// ---- Global part (the table everyone queries) ----
-
 /// A counter entry in the global table
 #[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
 pub struct CounterEntry<T: CountedItem> {
@ -46,28 +39,6 @@ mod v08 {
 	pub values: BTreeMap<String, CounterValue>,
 }

-	/// A counter entry in the global table
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct CounterValue {
-		pub node_values: BTreeMap<Uuid, (u64, i64)>,
-	}
-
-	impl<T: CountedItem> garage_util::migrate::InitialFormat for CounterEntry<T> {}
-
-	// ---- Local part (the counter we maintain transactionnaly on each node) ----
-
-	#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
-	pub(super) struct LocalCounterEntry<T: CountedItem> {
-		pub(super) pk: T::CP,
-		pub(super) sk: T::CS,
-		pub(super) values: BTreeMap<String, (u64, i64)>,
-	}
-
-	impl<T: CountedItem> garage_util::migrate::InitialFormat for LocalCounterEntry<T> {}
-}
-
-pub use v08::*;
-
 impl<T: CountedItem> Entry<T::CP, T::CS> for CounterEntry<T> {
 	fn partition_key(&self) -> &T::CP {
 		&self.pk
@ -109,6 +80,12 @@ impl<T: CountedItem> CounterEntry<T> {
 	}
 }

+/// A counter entry in the global table
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct CounterValue {
+	pub node_values: BTreeMap<Uuid, (u64, i64)>,
+}
+
 impl<T: CountedItem> Crdt for CounterEntry<T> {
 	fn merge(&mut self, other: &Self) {
 		for (name, e2) in other.values.iter() {
@ -165,6 +142,7 @@ impl<T: CountedItem> TableSchema for CounterTable<T> {
 pub struct IndexCounter<T: CountedItem> {
 	this_node: Uuid,
 	local_counter: db::Tree,
+	propagate_tx: mpsc::UnboundedSender<(T::CP, T::CS, LocalCounterEntry<T>)>,
 	pub table: Arc<Table<CounterTable<T>, TableShardedReplication>>,
 }

@ -174,11 +152,16 @@ impl<T: CountedItem> IndexCounter<T> {
 		replication: TableShardedReplication,
 		db: &db::Db,
 	) -> Arc<Self> {
-		Arc::new(Self {
+		let background = system.background.clone();
+
+		let (propagate_tx, propagate_rx) = mpsc::unbounded_channel();
+
+		let this = Arc::new(Self {
 			this_node: system.id,
 			local_counter: db
 				.open_tree(format!("local_counter_v2:{}", T::COUNTER_TABLE_NAME))
 				.expect("Unable to open local counter tree"),
+			propagate_tx,
 			table: Table::new(
 				CounterTable {
 					_phantom_t: Default::default(),
@ -187,11 +170,16 @@ impl<T: CountedItem> IndexCounter<T> {
 				system,
 				db,
 			),
-		})
-	}
+		});

-	pub fn spawn_workers(&self, bg: &BackgroundRunner) {
-		self.table.spawn_workers(bg);
+		background.spawn_worker(IndexPropagatorWorker {
+			index_counter: this.clone(),
+			propagate_rx,
+			buf: HashMap::new(),
+			errors: 0,
+		});
+
+		this
 	}

 	pub fn count(
@ -220,9 +208,11 @@ impl<T: CountedItem> IndexCounter<T> {
 		let tree_key = self.table.data.tree_key(pk, sk);

 		let mut entry = match tx.get(&self.local_counter, &tree_key[..])? {
-			Some(old_bytes) => LocalCounterEntry::<T>::decode(&old_bytes)
-				.ok_or_message("Cannot decode local counter entry")
-				.map_err(db::TxError::Abort)?,
+			Some(old_bytes) => {
+				rmp_serde::decode::from_read_ref::<_, LocalCounterEntry<T>>(&old_bytes)
+					.map_err(Error::RmpDecode)
+					.map_err(db::TxError::Abort)?
+			}
 			None => LocalCounterEntry {
 				pk: pk.clone(),
 				sk: sk.clone(),
@ -237,14 +227,17 @@ impl<T: CountedItem> IndexCounter<T> {
 			ent.1 += *inc;
 		}

-		let new_entry_bytes = entry
-			.encode()
+		let new_entry_bytes = rmp_to_vec_all_named(&entry)
 			.map_err(Error::RmpEncode)
 			.map_err(db::TxError::Abort)?;
 		tx.insert(&self.local_counter, &tree_key[..], new_entry_bytes)?;

-		let dist_entry = entry.into_counter_entry(self.this_node);
-		self.table.queue_insert(tx, &dist_entry)?;
+		if let Err(e) = self.propagate_tx.send((pk.clone(), sk.clone(), entry)) {
+			error!(
+				"Could not propagate updated counter values, failed to send to channel: {}",
+				e
+			);
+		}

 		Ok(())
 	}
@ -257,6 +250,23 @@ impl<T: CountedItem> IndexCounter<T> {
 		TS: TableSchema<E = T>,
 		TR: TableReplication,
 	{
+		let save_counter_entry = |entry: CounterEntry<T>| -> Result<(), Error> {
+			let entry_k = self
+				.table
+				.data
+				.tree_key(entry.partition_key(), entry.sort_key());
+			self.table
+				.data
+				.update_entry_with(&entry_k, |ent| match ent {
+					Some(mut ent) => {
+						ent.merge(&entry);
+						ent
+					}
+					None => entry.clone(),
+				})?;
+			Ok(())
+		};
+
 		// 1. Set all old local counters to zero
 		let now = now_msec();
 		let mut next_start: Option<Vec<u8>> = None;
@ -279,22 +289,20 @@ impl<T: CountedItem> IndexCounter<T> {

 			info!("zeroing old counters... ({})", hex::encode(&batch[0].0));
 			for (local_counter_k, local_counter) in batch {
-				let mut local_counter = LocalCounterEntry::<T>::decode(&local_counter)
-					.ok_or_message("Cannot decode local counter entry")?;
+				let mut local_counter =
+					rmp_serde::decode::from_read_ref::<_, LocalCounterEntry<T>>(&local_counter)?;

 				for (_, tv) in local_counter.values.iter_mut() {
 					tv.0 = std::cmp::max(tv.0 + 1, now);
 					tv.1 = 0;
 				}

-				let local_counter_bytes = local_counter.encode()?;
+				let local_counter_bytes = rmp_to_vec_all_named(&local_counter)?;
 				self.local_counter
 					.insert(&local_counter_k, &local_counter_bytes)?;

 				let counter_entry = local_counter.into_counter_entry(self.this_node);
-				self.local_counter
-					.db()
-					.transaction(|mut tx| self.table.queue_insert(&mut tx, &counter_entry))?;
+				save_counter_entry(counter_entry)?;

 				next_start = Some(local_counter_k);
 			}
@ -335,8 +343,9 @@ impl<T: CountedItem> IndexCounter<T> {
 				let local_counter_key = self.table.data.tree_key(pk, sk);
 				let mut local_counter = match self.local_counter.get(&local_counter_key)? {
 					Some(old_bytes) => {
-						let ent = LocalCounterEntry::<T>::decode(&old_bytes)
-							.ok_or_message("Cannot decode local counter entry")?;
+						let ent = rmp_serde::decode::from_read_ref::<_, LocalCounterEntry<T>>(
+							&old_bytes,
+						)?;
 						assert!(ent.pk == *pk);
 						assert!(ent.sk == *sk);
 						ent
@ -353,14 +362,12 @@ impl<T: CountedItem> IndexCounter<T> {
 					tv.1 += v;
 				}

-				let local_counter_bytes = local_counter.encode()?;
+				let local_counter_bytes = rmp_to_vec_all_named(&local_counter)?;
 				self.local_counter
 					.insert(&local_counter_key, local_counter_bytes)?;

 				let counter_entry = local_counter.into_counter_entry(self.this_node);
-				self.local_counter
-					.db()
-					.transaction(|mut tx| self.table.queue_insert(&mut tx, &counter_entry))?;
+				save_counter_entry(counter_entry)?;

 				next_start = Some(counted_entry_k);
 			}
@ -371,7 +378,104 @@ impl<T: CountedItem> IndexCounter<T> {
 	}
 }

-// ----
+struct IndexPropagatorWorker<T: CountedItem> {
+	index_counter: Arc<IndexCounter<T>>,
+	propagate_rx: mpsc::UnboundedReceiver<(T::CP, T::CS, LocalCounterEntry<T>)>,
+
+	buf: HashMap<Vec<u8>, CounterEntry<T>>,
+	errors: usize,
+}
+
+impl<T: CountedItem> IndexPropagatorWorker<T> {
+	fn add_ent(&mut self, pk: T::CP, sk: T::CS, counters: LocalCounterEntry<T>) {
+		let tree_key = self.index_counter.table.data.tree_key(&pk, &sk);
+		let dist_entry = counters.into_counter_entry(self.index_counter.this_node);
+		match self.buf.entry(tree_key) {
+			hash_map::Entry::Vacant(e) => {
+				e.insert(dist_entry);
+			}
+			hash_map::Entry::Occupied(mut e) => {
+				e.get_mut().merge(&dist_entry);
+			}
+		}
+	}
+}
+
+#[async_trait]
+impl<T: CountedItem> Worker for IndexPropagatorWorker<T> {
+	fn name(&self) -> String {
+		format!("{} index counter propagator", T::COUNTER_TABLE_NAME)
+	}
+
+	fn info(&self) -> Option<String> {
+		if !self.buf.is_empty() {
+			Some(format!("{} items in queue", self.buf.len()))
+		} else {
+			None
+		}
+	}
+
+	async fn work(&mut self, must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
+		// This loop batches updates to counters to be sent all at once.
+		// They are sent once the propagate_rx channel has been emptied (or is closed).
+		let closed = loop {
+			match self.propagate_rx.try_recv() {
+				Ok((pk, sk, counters)) => {
+					self.add_ent(pk, sk, counters);
+				}
+				Err(mpsc::error::TryRecvError::Empty) => break false,
+				Err(mpsc::error::TryRecvError::Disconnected) => break true,
+			}
+		};
+
+		if !self.buf.is_empty() {
+			let entries_k = self.buf.keys().take(100).cloned().collect::<Vec<_>>();
+			let entries = entries_k.iter().map(|k| self.buf.get(k).unwrap());
+			if let Err(e) = self.index_counter.table.insert_many(entries).await {
+				self.errors += 1;
+				if self.errors >= 2 && *must_exit.borrow() {
+					error!("({}) Could not propagate {} counter values: {}, these counters will not be updated correctly.", T::COUNTER_TABLE_NAME, self.buf.len(), e);
+					return Ok(WorkerState::Done);
+				}
+				// Propagate error up to worker manager, it will log it, increment a counter,
+				// and sleep for a certain delay (with exponential backoff), waiting for
+				// things to go back to normal
+				return Err(e);
+			} else {
+				for k in entries_k {
+					self.buf.remove(&k);
+				}
+				self.errors = 0;
+			}
+
+			return Ok(WorkerState::Busy);
+		} else if closed {
+			return Ok(WorkerState::Done);
+		} else {
+			return Ok(WorkerState::Idle);
+		}
+	}
+
+	async fn wait_for_work(&mut self, _must_exit: &watch::Receiver<bool>) -> WorkerState {
+		match self.propagate_rx.recv().await {
+			Some((pk, sk, counters)) => {
+				self.add_ent(pk, sk, counters);
+				WorkerState::Busy
+			}
+			None => match self.buf.is_empty() {
+				false => WorkerState::Busy,
+				true => WorkerState::Done,
+			},
+		}
+	}
+}
+
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+struct LocalCounterEntry<T: CountedItem> {
+	pk: T::CP,
+	sk: T::CS,
+	values: BTreeMap<String, (u64, i64)>,
+}

 impl<T: CountedItem> LocalCounterEntry<T> {
 	fn into_counter_entry(self, this_node: Uuid) -> CounterEntry<T> {
--- a/src/model/k2v/item_table.rs
+++ b/src/model/k2v/item_table.rs
@ -1,8 +1,7 @@
+use serde::{Deserialize, Serialize};
 use std::collections::BTreeMap;
 use std::sync::Arc;

-use serde::{Deserialize, Serialize};
-
 use garage_db as db;
 use garage_util::data::*;

@ -18,18 +17,12 @@ pub const CONFLICTS: &str = "conflicts";
 pub const VALUES: &str = "values";
 pub const BYTES: &str = "bytes";

-mod v08 {
-	use crate::k2v::causality::K2VNodeId;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-	use std::collections::BTreeMap;
-
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
 pub struct K2VItem {
 	pub partition: K2VItemPartition,
 	pub sort_key: String,

-		pub(super) items: BTreeMap<K2VNodeId, DvvsEntry>,
+	items: BTreeMap<K2VNodeId, DvvsEntry>,
 }

 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize, Hash)]
@ -39,9 +32,9 @@ mod v08 {
 }

 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct DvvsEntry {
-		pub(super) t_discard: u64,
-		pub(super) values: Vec<(u64, DvvsValue)>,
+struct DvvsEntry {
+	t_discard: u64,
+	values: Vec<(u64, DvvsValue)>,
 }

 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
@ -50,11 +43,6 @@ mod v08 {
 	Deleted,
 }

-	impl garage_util::migrate::InitialFormat for K2VItem {}
-}
-
-pub use v08::*;
-
 impl K2VItem {
 	/// Creates a new K2VItem when no previous entry existed in the db
 	pub fn new(bucket_id: Uuid, partition_key: String, sort_key: String) -> Self {
--- a/src/model/k2v/rpc.rs
+++ b/src/model/k2v/rpc.rs
@ -273,9 +273,14 @@ impl K2VRpcHandler {
 	}

 	fn local_insert(&self, item: &InsertedItem) -> Result<Option<K2VItem>, Error> {
+		let tree_key = self
+			.item_table
+			.data
+			.tree_key(&item.partition, &item.sort_key);
+
 		self.item_table
 			.data
-			.update_entry_with(&item.partition, &item.sort_key, |ent| {
+			.update_entry_with(&tree_key[..], |ent| {
 				let mut ent = ent.unwrap_or_else(|| {
 					K2VItem::new(
 						item.partition.bucket_id,
--- a/src/model/key_table.rs
+++ b/src/model/key_table.rs
@ -1,58 +1,12 @@
 use serde::{Deserialize, Serialize};

-use garage_util::crdt::{self, Crdt};
+use garage_table::crdt::*;
+use garage_table::*;
 use garage_util::data::*;

-use garage_table::{DeletedFilter, EmptyKey, Entry, TableSchema};
-
 use crate::permission::BucketKeyPerm;

-pub(crate) mod v05 {
-	use garage_util::crdt;
-	use serde::{Deserialize, Serialize};
-
-	/// An api key
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct Key {
-		/// The id of the key (immutable), used as partition key
-		pub key_id: String,
-
-		/// The secret_key associated
-		pub secret_key: String,
-
-		/// Name for the key
-		pub name: crdt::Lww<String>,
-
-		/// Is the key deleted
-		pub deleted: crdt::Bool,
-
-		/// Buckets in which the key is authorized. Empty if `Key` is deleted
-		// CRDT interaction: deleted implies authorized_buckets is empty
-		pub authorized_buckets: crdt::LwwMap<String, PermissionSet>,
-	}
-
-	/// Permission given to a key in a bucket
-	#[derive(PartialOrd, Ord, PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct PermissionSet {
-		/// The key can be used to read the bucket
-		pub allow_read: bool,
-		/// The key can be used to write in the bucket
-		pub allow_write: bool,
-	}
-
-	impl crdt::AutoCrdt for PermissionSet {
-		const WARN_IF_DIFFERENT: bool = true;
-	}
-
-	impl garage_util::migrate::InitialFormat for Key {}
-}
-
-mod v08 {
-	use super::v05;
-	use crate::permission::BucketKeyPerm;
-	use garage_util::crdt;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
+use crate::prev::v051::key_table as old;

 /// An api key
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
@ -86,36 +40,6 @@ mod v08 {
 	pub local_aliases: crdt::LwwMap<String, Option<Uuid>>,
 }

-	impl garage_util::migrate::Migrate for Key {
-		type Previous = v05::Key;
-
-		fn migrate(old_k: v05::Key) -> Key {
-			let name = crdt::Lww::raw(old_k.name.timestamp(), old_k.name.get().clone());
-
-			let state = if old_k.deleted.get() {
-				crdt::Deletable::Deleted
-			} else {
-				// Authorized buckets is ignored here,
-				// migration is performed in specific migration code in
-				// garage/migrate.rs
-				crdt::Deletable::Present(KeyParams {
-					secret_key: old_k.secret_key,
-					name,
-					allow_create_bucket: crdt::Lww::new(false),
-					authorized_buckets: crdt::Map::new(),
-					local_aliases: crdt::LwwMap::new(),
-				})
-			};
-			Key {
-				key_id: old_k.key_id,
-				state,
-			}
-		}
-	}
-}
-
-pub use v08::*;
-
 impl KeyParams {
 	fn new(secret_key: &str, name: &str) -> Self {
 		KeyParams {
@ -249,4 +173,28 @@ impl TableSchema for KeyTable {
 			}
 		}
 	}
+
+	fn try_migrate(bytes: &[u8]) -> Option<Self::E> {
+		let old_k = rmp_serde::decode::from_read_ref::<_, old::Key>(bytes).ok()?;
+		let name = crdt::Lww::raw(old_k.name.timestamp(), old_k.name.get().clone());
+
+		let state = if old_k.deleted.get() {
+			crdt::Deletable::Deleted
+		} else {
+			// Authorized buckets is ignored here,
+			// migration is performed in specific migration code in
+			// garage/migrate.rs
+			crdt::Deletable::Present(KeyParams {
+				secret_key: old_k.secret_key,
+				name,
+				allow_create_bucket: crdt::Lww::new(false),
+				authorized_buckets: crdt::Map::new(),
+				local_aliases: crdt::LwwMap::new(),
+			})
+		};
+		Some(Key {
+			key_id: old_k.key_id,
+			state,
+		})
+	}
 }
--- a/src/model/migrate.rs
+++ b/src/model/migrate.rs
@ -2,7 +2,6 @@ use std::sync::Arc;

 use garage_util::crdt::*;
 use garage_util::data::*;
-use garage_util::encode::nonversioned_decode;
 use garage_util::error::Error as GarageError;
 use garage_util::time::*;

@ -29,8 +28,8 @@ impl Migrate {
 		let mut old_buckets = vec![];
 		for res in tree.iter().map_err(GarageError::from)? {
 			let (_k, v) = res.map_err(GarageError::from)?;
-			let bucket =
-				nonversioned_decode::<old_bucket::Bucket>(&v[..]).map_err(GarageError::from)?;
+			let bucket = rmp_serde::decode::from_read_ref::<_, old_bucket::Bucket>(&v[..])
+				.map_err(GarageError::from)?;
 			old_buckets.push(bucket);
 		}

--- a/src/model/prev/v051/bucket_table.rs
+++ b/src/model/prev/v051/bucket_table.rs
@ -3,7 +3,7 @@ use serde::{Deserialize, Serialize};
 use garage_table::crdt::Crdt;
 use garage_table::*;

-use crate::key_table::v05::PermissionSet;
+use super::key_table::PermissionSet;

 /// A bucket is a collection of objects
 ///
--- a/src/model/prev/v051/key_table.rs
+++ b/src/model/prev/v051/key_table.rs
@ -0,0 +1,50 @@
+use serde::{Deserialize, Serialize};
+
+use garage_table::crdt::*;
+use garage_table::*;
+
+/// An api key
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct Key {
+	/// The id of the key (immutable), used as partition key
+	pub key_id: String,
+
+	/// The secret_key associated
+	pub secret_key: String,
+
+	/// Name for the key
+	pub name: crdt::Lww<String>,
+
+	/// Is the key deleted
+	pub deleted: crdt::Bool,
+
+	/// Buckets in which the key is authorized. Empty if `Key` is deleted
+	// CRDT interaction: deleted implies authorized_buckets is empty
+	pub authorized_buckets: crdt::LwwMap<String, PermissionSet>,
+}
+
+/// Permission given to a key in a bucket
+#[derive(PartialOrd, Ord, PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct PermissionSet {
+	/// The key can be used to read the bucket
+	pub allow_read: bool,
+	/// The key can be used to write in the bucket
+	pub allow_write: bool,
+}
+
+impl AutoCrdt for PermissionSet {
+	const WARN_IF_DIFFERENT: bool = true;
+}
+
+impl Crdt for Key {
+	fn merge(&mut self, other: &Self) {
+		self.name.merge(&other.name);
+		self.deleted.merge(&other.deleted);
+
+		if self.deleted.get() {
+			self.authorized_buckets.clear();
+		} else {
+			self.authorized_buckets.merge(&other.authorized_buckets);
+		}
+	}
+}
--- a/src/model/prev/v051/mod.rs
+++ b/src/model/prev/v051/mod.rs
@ -1 +1,4 @@
 pub(crate) mod bucket_table;
+pub(crate) mod key_table;
+pub(crate) mod object_table;
+pub(crate) mod version_table;
--- a/src/model/prev/v051/object_table.rs
+++ b/src/model/prev/v051/object_table.rs
@ -0,0 +1,149 @@
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
+
+use garage_util::data::*;
+
+use garage_table::crdt::*;
+
+/// An object
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct Object {
+	/// The bucket in which the object is stored, used as partition key
+	pub bucket: String,
+
+	/// The key at which the object is stored in its bucket, used as sorting key
+	pub key: String,
+
+	/// The list of currenty stored versions of the object
+	versions: Vec<ObjectVersion>,
+}
+
+impl Object {
+	/// Get a list of currently stored versions of `Object`
+	pub fn versions(&self) -> &[ObjectVersion] {
+		&self.versions[..]
+	}
+}
+
+/// Informations about a version of an object
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersion {
+	/// Id of the version
+	pub uuid: Uuid,
+	/// Timestamp of when the object was created
+	pub timestamp: u64,
+	/// State of the version
+	pub state: ObjectVersionState,
+}
+
+/// State of an object version
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub enum ObjectVersionState {
+	/// The version is being received
+	Uploading(ObjectVersionHeaders),
+	/// The version is fully received
+	Complete(ObjectVersionData),
+	/// The version uploaded containded errors or the upload was explicitly aborted
+	Aborted,
+}
+
+impl Crdt for ObjectVersionState {
+	fn merge(&mut self, other: &Self) {
+		use ObjectVersionState::*;
+		match other {
+			Aborted => {
+				*self = Aborted;
+			}
+			Complete(b) => match self {
+				Aborted => {}
+				Complete(a) => {
+					a.merge(b);
+				}
+				Uploading(_) => {
+					*self = Complete(b.clone());
+				}
+			},
+			Uploading(_) => {}
+		}
+	}
+}
+
+/// Data stored in object version
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub enum ObjectVersionData {
+	/// The object was deleted, this Version is a tombstone to mark it as such
+	DeleteMarker,
+	/// The object is short, it's stored inlined
+	Inline(ObjectVersionMeta, #[serde(with = "serde_bytes")] Vec<u8>),
+	/// The object is not short, Hash of first block is stored here, next segments hashes are
+	/// stored in the version table
+	FirstBlock(ObjectVersionMeta, Hash),
+}
+
+impl AutoCrdt for ObjectVersionData {
+	const WARN_IF_DIFFERENT: bool = true;
+}
+
+/// Metadata about the object version
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersionMeta {
+	/// Headers to send to the client
+	pub headers: ObjectVersionHeaders,
+	/// Size of the object
+	pub size: u64,
+	/// etag of the object
+	pub etag: String,
+}
+
+/// Additional headers for an object
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersionHeaders {
+	/// Content type of the object
+	pub content_type: String,
+	/// Any other http headers to send
+	pub other: BTreeMap<String, String>,
+}
+
+impl ObjectVersion {
+	fn cmp_key(&self) -> (u64, Uuid) {
+		(self.timestamp, self.uuid)
+	}
+
+	/// Is the object version completely received
+	pub fn is_complete(&self) -> bool {
+		matches!(self.state, ObjectVersionState::Complete(_))
+	}
+}
+
+impl Crdt for Object {
+	fn merge(&mut self, other: &Self) {
+		// Merge versions from other into here
+		for other_v in other.versions.iter() {
+			match self
+				.versions
+				.binary_search_by(|v| v.cmp_key().cmp(&other_v.cmp_key()))
+			{
+				Ok(i) => {
+					self.versions[i].state.merge(&other_v.state);
+				}
+				Err(i) => {
+					self.versions.insert(i, other_v.clone());
+				}
+			}
+		}
+
+		// Remove versions which are obsolete, i.e. those that come
+		// before the last version which .is_complete().
+		let last_complete = self
+			.versions
+			.iter()
+			.enumerate()
+			.rev()
+			.find(|(_, v)| v.is_complete())
+			.map(|(vi, _)| vi);
+
+		if let Some(last_vi) = last_complete {
+			self.versions = self.versions.drain(last_vi..).collect::<Vec<_>>();
+		}
+	}
+}
--- a/src/model/prev/v051/version_table.rs
+++ b/src/model/prev/v051/version_table.rs
@ -0,0 +1,79 @@
+use serde::{Deserialize, Serialize};
+
+use garage_util::data::*;
+
+use garage_table::crdt::*;
+use garage_table::*;
+
+/// A version of an object
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct Version {
+	/// UUID of the version, used as partition key
+	pub uuid: Uuid,
+
+	// Actual data: the blocks for this version
+	// In the case of a multipart upload, also store the etags
+	// of individual parts and check them when doing CompleteMultipartUpload
+	/// Is this version deleted
+	pub deleted: crdt::Bool,
+	/// list of blocks of data composing the version
+	pub blocks: crdt::Map<VersionBlockKey, VersionBlock>,
+	/// Etag of each part in case of a multipart upload, empty otherwise
+	pub parts_etags: crdt::Map<u64, String>,
+
+	// Back link to bucket+key so that we can figure if
+	// this was deleted later on
+	/// Bucket in which the related object is stored
+	pub bucket: String,
+	/// Key in which the related object is stored
+	pub key: String,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, Debug, Serialize, Deserialize)]
+pub struct VersionBlockKey {
+	/// Number of the part
+	pub part_number: u64,
+	/// Offset of this sub-segment in its part
+	pub offset: u64,
+}
+
+impl Ord for VersionBlockKey {
+	fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+		self.part_number
+			.cmp(&other.part_number)
+			.then(self.offset.cmp(&other.offset))
+	}
+}
+
+impl PartialOrd for VersionBlockKey {
+	fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+		Some(self.cmp(other))
+	}
+}
+
+/// Informations about a single block
+#[derive(PartialEq, Eq, Ord, PartialOrd, Clone, Copy, Debug, Serialize, Deserialize)]
+pub struct VersionBlock {
+	/// Blake2 sum of the block
+	pub hash: Hash,
+	/// Size of the block
+	pub size: u64,
+}
+
+impl AutoCrdt for VersionBlock {
+	const WARN_IF_DIFFERENT: bool = true;
+}
+
+impl Crdt for Version {
+	fn merge(&mut self, other: &Self) {
+		self.deleted.merge(&other.deleted);
+
+		if self.deleted.get() {
+			self.blocks.clear();
+			self.parts_etags.clear();
+		} else {
+			self.blocks.merge(&other.blocks);
+			self.parts_etags.merge(&other.parts_etags);
+		}
+	}
+}
--- a/src/model/s3/block_ref_table.rs
+++ b/src/model/s3/block_ref_table.rs
@ -1,3 +1,4 @@
+use serde::{Deserialize, Serialize};
 use std::sync::Arc;

 use garage_db as db;
@ -9,11 +10,6 @@ use garage_table::*;

 use garage_block::manager::*;

-mod v08 {
-	use garage_util::crdt;
-	use garage_util::data::{Hash, Uuid};
-	use serde::{Deserialize, Serialize};
-
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
 pub struct BlockRef {
 	/// Hash (blake2 sum) of the block, used as partition key
@ -27,11 +23,6 @@ mod v08 {
 	pub deleted: crdt::Bool,
 }

-	impl garage_util::migrate::InitialFormat for BlockRef {}
-}
-
-pub use v08::*;
-
 impl Entry<Hash, Uuid> for BlockRef {
 	fn partition_key(&self) -> &Hash {
 		&self.block
--- a/src/model/s3/object_table.rs
+++ b/src/model/s3/object_table.rs
@ -1,8 +1,10 @@
 use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
 use std::sync::Arc;

 use garage_db as db;

+use garage_util::background::BackgroundRunner;
 use garage_util::data::*;

 use garage_table::crdt::*;
@ -12,96 +14,12 @@ use garage_table::*;
 use crate::index_counter::*;
 use crate::s3::version_table::*;

+use crate::prev::v051::object_table as old;
+
 pub const OBJECTS: &str = "objects";
 pub const UNFINISHED_UPLOADS: &str = "unfinished_uploads";
 pub const BYTES: &str = "bytes";

-mod v05 {
-	use garage_util::data::{Hash, Uuid};
-	use serde::{Deserialize, Serialize};
-	use std::collections::BTreeMap;
-
-	/// An object
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct Object {
-		/// The bucket in which the object is stored, used as partition key
-		pub bucket: String,
-
-		/// The key at which the object is stored in its bucket, used as sorting key
-		pub key: String,
-
-		/// The list of currenty stored versions of the object
-		pub(super) versions: Vec<ObjectVersion>,
-	}
-
-	/// Informations about a version of an object
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct ObjectVersion {
-		/// Id of the version
-		pub uuid: Uuid,
-		/// Timestamp of when the object was created
-		pub timestamp: u64,
-		/// State of the version
-		pub state: ObjectVersionState,
-	}
-
-	/// State of an object version
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub enum ObjectVersionState {
-		/// The version is being received
-		Uploading(ObjectVersionHeaders),
-		/// The version is fully received
-		Complete(ObjectVersionData),
-		/// The version uploaded containded errors or the upload was explicitly aborted
-		Aborted,
-	}
-
-	/// Data stored in object version
-	#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
-	pub enum ObjectVersionData {
-		/// The object was deleted, this Version is a tombstone to mark it as such
-		DeleteMarker,
-		/// The object is short, it's stored inlined
-		Inline(ObjectVersionMeta, #[serde(with = "serde_bytes")] Vec<u8>),
-		/// The object is not short, Hash of first block is stored here, next segments hashes are
-		/// stored in the version table
-		FirstBlock(ObjectVersionMeta, Hash),
-	}
-
-	/// Metadata about the object version
-	#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
-	pub struct ObjectVersionMeta {
-		/// Headers to send to the client
-		pub headers: ObjectVersionHeaders,
-		/// Size of the object
-		pub size: u64,
-		/// etag of the object
-		pub etag: String,
-	}
-
-	/// Additional headers for an object
-	#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
-	pub struct ObjectVersionHeaders {
-		/// Content type of the object
-		pub content_type: String,
-		/// Any other http headers to send
-		pub other: BTreeMap<String, String>,
-	}
-
-	impl garage_util::migrate::InitialFormat for Object {}
-}
-
-mod v08 {
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-
-	use super::v05;
-
-	pub use v05::{
-		ObjectVersion, ObjectVersionData, ObjectVersionHeaders, ObjectVersionMeta,
-		ObjectVersionState,
-	};
-
 /// An object
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
 pub struct Object {
@ -112,26 +30,9 @@ mod v08 {
 	pub key: String,

 	/// The list of currenty stored versions of the object
-		pub(super) versions: Vec<ObjectVersion>,
+	versions: Vec<ObjectVersion>,
 }

-	impl garage_util::migrate::Migrate for Object {
-		type Previous = v05::Object;
-
-		fn migrate(old: v05::Object) -> Object {
-			use garage_util::data::blake2sum;
-
-			Object {
-				bucket_id: blake2sum(old.bucket.as_bytes()),
-				key: old.key,
-				versions: old.versions,
-			}
-		}
-	}
-}
-
-pub use v08::*;
-
 impl Object {
 	/// Initialize an Object struct from parts
 	pub fn new(bucket_id: Uuid, key: String, versions: Vec<ObjectVersion>) -> Self {
@ -168,6 +69,28 @@ impl Object {
 	}
 }

+/// Informations about a version of an object
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersion {
+	/// Id of the version
+	pub uuid: Uuid,
+	/// Timestamp of when the object was created
+	pub timestamp: u64,
+	/// State of the version
+	pub state: ObjectVersionState,
+}
+
+/// State of an object version
+#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
+pub enum ObjectVersionState {
+	/// The version is being received
+	Uploading(ObjectVersionHeaders),
+	/// The version is fully received
+	Complete(ObjectVersionData),
+	/// The version uploaded containded errors or the upload was explicitly aborted
+	Aborted,
+}
+
 impl Crdt for ObjectVersionState {
 	fn merge(&mut self, other: &Self) {
 		use ObjectVersionState::*;
@ -189,10 +112,42 @@ impl Crdt for ObjectVersionState {
 	}
 }

+/// Data stored in object version
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub enum ObjectVersionData {
+	/// The object was deleted, this Version is a tombstone to mark it as such
+	DeleteMarker,
+	/// The object is short, it's stored inlined
+	Inline(ObjectVersionMeta, #[serde(with = "serde_bytes")] Vec<u8>),
+	/// The object is not short, Hash of first block is stored here, next segments hashes are
+	/// stored in the version table
+	FirstBlock(ObjectVersionMeta, Hash),
+}
+
 impl AutoCrdt for ObjectVersionData {
 	const WARN_IF_DIFFERENT: bool = true;
 }

+/// Metadata about the object version
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersionMeta {
+	/// Headers to send to the client
+	pub headers: ObjectVersionHeaders,
+	/// Size of the object
+	pub size: u64,
+	/// etag of the object
+	pub etag: String,
+}
+
+/// Additional headers for an object
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
+pub struct ObjectVersionHeaders {
+	/// Content type of the object
+	pub content_type: String,
+	/// Any other http headers to send
+	pub other: BTreeMap<String, String>,
+}
+
 impl ObjectVersion {
 	fn cmp_key(&self) -> (u64, Uuid) {
 		(self.timestamp, self.uuid)
@ -266,6 +221,7 @@ impl Crdt for Object {
 }

 pub struct ObjectTable {
+	pub background: Arc<BackgroundRunner>,
 	pub version_table: Arc<Table<VersionTable, TableShardedReplication>>,
 	pub object_counter_table: Arc<IndexCounter<Object>>,
 }
@ -299,7 +255,12 @@ impl TableSchema for ObjectTable {
 			);
 		}

-		// 2. Enqueue propagation deletions to version table
+		// 2. Spawn threads that propagates deletions to version table
+		let version_table = self.version_table.clone();
+		let old = old.cloned();
+		let new = new.cloned();
+
+		self.background.spawn(async move {
 			if let (Some(old_v), Some(new_v)) = (old, new) {
 				// Propagate deletion of old versions
 				for v in old_v.versions.iter() {
@ -316,17 +277,12 @@ impl TableSchema for ObjectTable {
 					if newly_deleted {
 						let deleted_version =
 							Version::new(v.uuid, old_v.bucket_id, old_v.key.clone(), true);
-					let res = self.version_table.queue_insert(tx, &deleted_version);
-					if let Err(e) = db::unabort(res)? {
-						error!(
-							"Unable to enqueue version deletion propagation: {}. A repair will be needed.",
-							e
-						);
+						version_table.insert(&deleted_version).await?;
 					}
 				}
 			}
-		}
-
+			Ok(())
+		});
 		Ok(())
 	}

@ -336,6 +292,11 @@ impl TableSchema for ObjectTable {
 			ObjectFilter::IsUploading => entry.versions.iter().any(|v| v.is_uploading()),
 		}
 	}
+
+	fn try_migrate(bytes: &[u8]) -> Option<Self::E> {
+		let old_obj = rmp_serde::decode::from_read_ref::<_, old::Object>(bytes).ok()?;
+		Some(migrate_object(old_obj))
+	}
 }

 impl CountedItem for Object {
@ -380,3 +341,64 @@ impl CountedItem for Object {
 		]
 	}
 }
+
+// vvvvvvvv migration code, stupid stuff vvvvvvvvvvvv
+// (we just want to change bucket into bucket_id by hashing it)
+
+fn migrate_object(o: old::Object) -> Object {
+	let versions = o
+		.versions()
+		.iter()
+		.cloned()
+		.map(migrate_object_version)
+		.collect();
+	Object {
+		bucket_id: blake2sum(o.bucket.as_bytes()),
+		key: o.key,
+		versions,
+	}
+}
+
+fn migrate_object_version(v: old::ObjectVersion) -> ObjectVersion {
+	ObjectVersion {
+		uuid: Uuid::try_from(v.uuid.as_slice()).unwrap(),
+		timestamp: v.timestamp,
+		state: match v.state {
+			old::ObjectVersionState::Uploading(h) => {
+				ObjectVersionState::Uploading(migrate_object_version_headers(h))
+			}
+			old::ObjectVersionState::Complete(d) => {
+				ObjectVersionState::Complete(migrate_object_version_data(d))
+			}
+			old::ObjectVersionState::Aborted => ObjectVersionState::Aborted,
+		},
+	}
+}
+
+fn migrate_object_version_headers(h: old::ObjectVersionHeaders) -> ObjectVersionHeaders {
+	ObjectVersionHeaders {
+		content_type: h.content_type,
+		other: h.other,
+	}
+}
+
+fn migrate_object_version_data(d: old::ObjectVersionData) -> ObjectVersionData {
+	match d {
+		old::ObjectVersionData::DeleteMarker => ObjectVersionData::DeleteMarker,
+		old::ObjectVersionData::Inline(m, b) => {
+			ObjectVersionData::Inline(migrate_object_version_meta(m), b)
+		}
+		old::ObjectVersionData::FirstBlock(m, h) => ObjectVersionData::FirstBlock(
+			migrate_object_version_meta(m),
+			Hash::try_from(h.as_slice()).unwrap(),
+		),
+	}
+}
+
+fn migrate_object_version_meta(m: old::ObjectVersionMeta) -> ObjectVersionMeta {
+	ObjectVersionMeta {
+		headers: migrate_object_version_headers(m.headers),
+		size: m.size,
+		etag: m.etag,
+	}
+}
--- a/src/model/s3/version_table.rs
+++ b/src/model/s3/version_table.rs
@ -1,7 +1,9 @@
+use serde::{Deserialize, Serialize};
 use std::sync::Arc;

 use garage_db as db;

+use garage_util::background::BackgroundRunner;
 use garage_util::data::*;

 use garage_table::crdt::*;
@ -10,61 +12,7 @@ use garage_table::*;

 use crate::s3::block_ref_table::*;

-mod v05 {
-	use garage_util::crdt;
-	use garage_util::data::{Hash, Uuid};
-	use serde::{Deserialize, Serialize};
-
-	/// A version of an object
-	#[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
-	pub struct Version {
-		/// UUID of the version, used as partition key
-		pub uuid: Uuid,
-
-		// Actual data: the blocks for this version
-		// In the case of a multipart upload, also store the etags
-		// of individual parts and check them when doing CompleteMultipartUpload
-		/// Is this version deleted
-		pub deleted: crdt::Bool,
-		/// list of blocks of data composing the version
-		pub blocks: crdt::Map<VersionBlockKey, VersionBlock>,
-		/// Etag of each part in case of a multipart upload, empty otherwise
-		pub parts_etags: crdt::Map<u64, String>,
-
-		// Back link to bucket+key so that we can figure if
-		// this was deleted later on
-		/// Bucket in which the related object is stored
-		pub bucket: String,
-		/// Key in which the related object is stored
-		pub key: String,
-	}
-
-	#[derive(PartialEq, Eq, Clone, Copy, Debug, Serialize, Deserialize)]
-	pub struct VersionBlockKey {
-		/// Number of the part
-		pub part_number: u64,
-		/// Offset of this sub-segment in its part
-		pub offset: u64,
-	}
-
-	/// Informations about a single block
-	#[derive(PartialEq, Eq, Ord, PartialOrd, Clone, Copy, Debug, Serialize, Deserialize)]
-	pub struct VersionBlock {
-		/// Blake2 sum of the block
-		pub hash: Hash,
-		/// Size of the block
-		pub size: u64,
-	}
-
-	impl garage_util::migrate::InitialFormat for Version {}
-}
-
-mod v08 {
-	use garage_util::crdt;
-	use garage_util::data::Uuid;
-	use serde::{Deserialize, Serialize};
-
-	use super::v05;
+use crate::prev::v051::version_table as old;

 /// A version of an object
 #[derive(PartialEq, Eq, Clone, Debug, Serialize, Deserialize)]
@ -90,28 +38,6 @@ mod v08 {
 	pub key: String,
 }

-	pub use v05::{VersionBlock, VersionBlockKey};
-
-	impl garage_util::migrate::Migrate for Version {
-		type Previous = v05::Version;
-
-		fn migrate(old: v05::Version) -> Version {
-			use garage_util::data::blake2sum;
-
-			Version {
-				uuid: old.uuid,
-				deleted: old.deleted,
-				blocks: old.blocks,
-				parts_etags: old.parts_etags,
-				bucket_id: blake2sum(old.bucket.as_bytes()),
-				key: old.key,
-			}
-		}
-	}
-}
-
-pub use v08::*;
-
 impl Version {
 	pub fn new(uuid: Uuid, bucket_id: Uuid, key: String, deleted: bool) -> Self {
 		Self {
@ -139,6 +65,14 @@ impl Version {
 	}
 }

+#[derive(PartialEq, Eq, Clone, Copy, Debug, Serialize, Deserialize)]
+pub struct VersionBlockKey {
+	/// Number of the part
+	pub part_number: u64,
+	/// Offset of this sub-segment in its part
+	pub offset: u64,
+}
+
 impl Ord for VersionBlockKey {
 	fn cmp(&self, other: &Self) -> std::cmp::Ordering {
 		self.part_number
@ -153,6 +87,15 @@ impl PartialOrd for VersionBlockKey {
 	}
 }

+/// Informations about a single block
+#[derive(PartialEq, Eq, Ord, PartialOrd, Clone, Copy, Debug, Serialize, Deserialize)]
+pub struct VersionBlock {
+	/// Blake2 sum of the block
+	pub hash: Hash,
+	/// Size of the block
+	pub size: u64,
+}
+
 impl AutoCrdt for VersionBlock {
 	const WARN_IF_DIFFERENT: bool = true;
 }
@ -184,6 +127,7 @@ impl Crdt for Version {
 }

 pub struct VersionTable {
+	pub background: Arc<BackgroundRunner>,
 	pub block_ref_table: Arc<Table<BlockRefTable, TableShardedReplication>>,
 }

@ -197,26 +141,33 @@ impl TableSchema for VersionTable {

 	fn updated(
 		&self,
-		tx: &mut db::Transaction,
+		_tx: &mut db::Transaction,
 		old: Option<&Self::E>,
 		new: Option<&Self::E>,
 	) -> db::TxOpResult<()> {
+		let block_ref_table = self.block_ref_table.clone();
+		let old = old.cloned();
+		let new = new.cloned();
+
+		self.background.spawn(async move {
 			if let (Some(old_v), Some(new_v)) = (old, new) {
 				// Propagate deletion of version blocks
 				if new_v.deleted.get() && !old_v.deleted.get() {
-				let deleted_block_refs = old_v.blocks.items().iter().map(|(_k, vb)| BlockRef {
+					let deleted_block_refs = old_v
+						.blocks
+						.items()
+						.iter()
+						.map(|(_k, vb)| BlockRef {
 							block: vb.hash,
 							version: old_v.uuid,
 							deleted: true.into(),
+						})
+						.collect::<Vec<_>>();
+					block_ref_table.insert_many(&deleted_block_refs[..]).await?;
+				}
+			}
+			Ok(())
 		});
-				for block_ref in deleted_block_refs {
-					let res = self.block_ref_table.queue_insert(tx, &block_ref);
-					if let Err(e) = db::unabort(res)? {
-						error!("Unable to enqueue block ref deletion propagation: {}. A repair will be needed.", e);
-					}
-				}
-			}
-		}

 		Ok(())
 	}
@ -224,4 +175,42 @@ impl TableSchema for VersionTable {
 	fn matches_filter(entry: &Self::E, filter: &Self::Filter) -> bool {
 		filter.apply(entry.deleted.get())
 	}
+
+	fn try_migrate(bytes: &[u8]) -> Option<Self::E> {
+		let old = rmp_serde::decode::from_read_ref::<_, old::Version>(bytes).ok()?;
+
+		let blocks = old
+			.blocks
+			.items()
+			.iter()
+			.map(|(k, v)| {
+				(
+					VersionBlockKey {
+						part_number: k.part_number,
+						offset: k.offset,
+					},
+					VersionBlock {
+						hash: Hash::try_from(v.hash.as_slice()).unwrap(),
+						size: v.size,
+					},
+				)
+			})
+			.collect::<crdt::Map<_, _>>();
+
+		let parts_etags = old
+			.parts_etags
+			.items()
+			.iter()
+			.map(|(k, v)| (*k, v.clone()))
+			.collect::<crdt::Map<_, _>>();
+
+		Some(Version {
+			uuid: Hash::try_from(old.uuid.as_slice()).unwrap(),
+			deleted: crdt::Bool::new(old.deleted.get()),
+			blocks,
+			parts_etags,
+			bucket_id: blake2sum(old.bucket.as_bytes()),
+			key: old.key,
+		})
+	}
 }
--- a/src/rpc/Cargo.toml
+++ b/src/rpc/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_rpc"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,7 +14,7 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_util = { version = "0.8.1", path = "../util" }
+garage_util = { version = "0.8.0", path = "../util" }

 arc-swap = "1.0"
 bytes = "1.0"
@ -25,6 +25,7 @@ rand = "0.8"
 sodiumoxide = { version = "0.2.5-0", package = "kuska-sodiumoxide" }

 async-trait = "0.1.7"
+rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"
 serde_json = "1.0"
--- a/src/rpc/layout.rs
+++ b/src/rpc/layout.rs
@ -5,7 +5,6 @@ use serde::{Deserialize, Serialize};

 use garage_util::crdt::{AutoCrdt, Crdt, LwwMap};
 use garage_util::data::*;
-use garage_util::encode::nonversioned_encode;
 use garage_util::error::*;

 use crate::ring::*;
@ -36,8 +35,6 @@ pub struct ClusterLayout {
 	pub staging_hash: Hash,
 }

-impl garage_util::migrate::InitialFormat for ClusterLayout {}
-
 #[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
 pub struct NodeRoleV(pub Option<NodeRole>);

@ -71,7 +68,7 @@ impl NodeRole {
 impl ClusterLayout {
 	pub fn new(replication_factor: usize) -> Self {
 		let empty_lwwmap = LwwMap::new();
-		let empty_lwwmap_hash = blake2sum(&nonversioned_encode(&empty_lwwmap).unwrap()[..]);
+		let empty_lwwmap_hash = blake2sum(&rmp_to_vec_all_named(&empty_lwwmap).unwrap()[..]);

 		ClusterLayout {
 			version: 0,
@ -93,7 +90,7 @@ impl ClusterLayout {
 			Ordering::Equal => {
 				self.staging.merge(&other.staging);

-				let new_staging_hash = blake2sum(&nonversioned_encode(&self.staging).unwrap()[..]);
+				let new_staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
 				let changed = new_staging_hash != self.staging_hash;

 				self.staging_hash = new_staging_hash;
@ -128,7 +125,7 @@ To know the correct value of the new layout version, invoke `garage layout show`
 		}

 		self.staging.clear();
-		self.staging_hash = blake2sum(&nonversioned_encode(&self.staging).unwrap()[..]);
+		self.staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);

 		self.version += 1;

@ -152,7 +149,7 @@ To know the correct value of the new layout version, invoke `garage layout show`
 		}

 		self.staging.clear();
-		self.staging_hash = blake2sum(&nonversioned_encode(&self.staging).unwrap()[..]);
+		self.staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);

 		self.version += 1;

@ -181,7 +178,7 @@ To know the correct value of the new layout version, invoke `garage layout show`
 	/// returns true if consistent, false if error
 	pub fn check(&self) -> bool {
 		// Check that the hash of the staging data is correct
-		let staging_hash = blake2sum(&nonversioned_encode(&self.staging).unwrap()[..]);
+		let staging_hash = blake2sum(&rmp_to_vec_all_named(&self.staging).unwrap()[..]);
 		if staging_hash != self.staging_hash {
 			return false;
 		}
--- a/src/rpc/lib.rs
+++ b/src/rpc/lib.rs
@ -17,5 +17,3 @@ mod metrics;
 pub mod rpc_helper;

 pub use rpc_helper::*;
-
-pub mod system_metrics;
--- a/src/rpc/rpc_helper.rs
+++ b/src/rpc/rpc_helper.rs
@ -5,6 +5,7 @@ use std::time::Duration;
 use futures::future::join_all;
 use futures::stream::futures_unordered::FuturesUnordered;
 use futures::stream::StreamExt;
+use futures_util::future::FutureExt;
 use tokio::select;
 use tokio::sync::watch;

@ -23,6 +24,7 @@ pub use netapp::message::{
 use netapp::peering::fullmesh::FullMeshPeeringStrategy;
 pub use netapp::{self, NetApp, NodeID};

+use garage_util::background::BackgroundRunner;
 use garage_util::data::*;
 use garage_util::error::Error;
 use garage_util::metrics::RecordDuration;
@ -92,6 +94,7 @@ pub struct RpcHelper(Arc<RpcHelperInner>);
 struct RpcHelperInner {
 	our_node_id: Uuid,
 	fullmesh: Arc<FullMeshPeeringStrategy>,
+	background: Arc<BackgroundRunner>,
 	ring: watch::Receiver<Arc<Ring>>,
 	metrics: RpcMetrics,
 	rpc_timeout: Duration,
@ -101,6 +104,7 @@ impl RpcHelper {
 	pub(crate) fn new(
 		our_node_id: Uuid,
 		fullmesh: Arc<FullMeshPeeringStrategy>,
+		background: Arc<BackgroundRunner>,
 		ring: watch::Receiver<Arc<Ring>>,
 		rpc_timeout: Option<Duration>,
 	) -> Self {
@ -109,6 +113,7 @@ impl RpcHelper {
 		Self(Arc::new(RpcHelperInner {
 			our_node_id,
 			fullmesh,
+			background,
 			ring,
 			metrics,
 			rpc_timeout: rpc_timeout.unwrap_or(DEFAULT_TIMEOUT),
@ -372,13 +377,16 @@ impl RpcHelper {

 			if !resp_stream.is_empty() {
 				// Continue remaining requests in background.
-				// Note: these requests can get interrupted on process shutdown,
-				// we must not count on them being executed for certain.
-				// For all background things that have to happen with certainty,
-				// they have to be put in a proper queue that is persisted to disk.
-				tokio::spawn(async move {
+				// Continue the remaining requests immediately using tokio::spawn
+				// but enqueue a task in the background runner
+				// to ensure that the process won't exit until the requests are done
+				// (if we had just enqueued the resp_stream.collect directly in the background runner,
+				// the requests might have been put on hold in the background runner's queue,
+				// in which case they might timeout or otherwise fail)
+				let wait_finished_fut = tokio::spawn(async move {
 					resp_stream.collect::<Vec<Result<_, _>>>().await;
 				});
+				self.0.background.spawn(wait_finished_fut.map(|_| Ok(())));
 			}
 		}

--- a/src/rpc/system.rs
+++ b/src/rpc/system.rs
@ -21,6 +21,7 @@ use netapp::peering::fullmesh::FullMeshPeeringStrategy;
 use netapp::util::parse_and_resolve_peer_addr_async;
 use netapp::{NetApp, NetworkKey, NodeID, NodeKey};

+use garage_util::background::BackgroundRunner;
 use garage_util::config::Config;
 #[cfg(feature = "kubernetes-discovery")]
 use garage_util::config::KubernetesDiscoveryConfig;
@ -38,9 +39,6 @@ use crate::replication_mode::*;
 use crate::ring::*;
 use crate::rpc_helper::*;

-#[cfg(feature = "metrics")]
-use crate::system_metrics::*;
-
 const DISCOVERY_INTERVAL: Duration = Duration::from_secs(60);
 const STATUS_EXCHANGE_INTERVAL: Duration = Duration::from_secs(10);

@ -52,6 +50,8 @@ pub const GARAGE_VERSION_TAG: u64 = 0x6761726167650008; // garage 0x0008
 /// RPC endpoint used for calls related to membership
 pub const SYSTEM_RPC_PATH: &str = "garage_rpc/membership.rs/SystemRpc";

+pub const CONNECT_ERROR_MESSAGE: &str = "Error establishing RPC connection to remote node. This can happen if the remote node is not reachable on the network, but also if the two nodes are not configured with the same rpc_secret";
+
 /// RPC messages related to membership
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum SystemRpc {
@ -76,17 +76,13 @@ impl Rpc for SystemRpc {
 	type Response = Result<SystemRpc, Error>;
 }

-#[derive(Serialize, Deserialize)]
-pub struct PeerList(Vec<(Uuid, SocketAddr)>);
-impl garage_util::migrate::InitialFormat for PeerList {}
-
 /// This node's membership manager
 pub struct System {
 	/// The id of this node
 	pub id: Uuid,

 	persist_cluster_layout: Persister<ClusterLayout>,
-	persist_peer_list: Persister<PeerList>,
+	persist_peer_list: Persister<Vec<(Uuid, SocketAddr)>>,

 	local_status: ArcSwap<NodeStatus>,
 	node_status: RwLock<HashMap<Uuid, (u64, NodeStatus)>>,
@ -106,8 +102,6 @@ pub struct System {
 	consul_discovery: Option<ConsulDiscovery>,
 	#[cfg(feature = "kubernetes-discovery")]
 	kubernetes_discovery: Option<KubernetesDiscoveryConfig>,
-	#[cfg(feature = "metrics")]
-	metrics: SystemMetrics,

 	replication_mode: ReplicationMode,
 	replication_factor: usize,
@ -116,6 +110,9 @@ pub struct System {
 	pub ring: watch::Receiver<Arc<Ring>>,
 	update_ring: Mutex<watch::Sender<Arc<Ring>>>,

+	/// The job runner of this node
+	pub background: Arc<BackgroundRunner>,
+
 	/// Path to metadata directory
 	pub metadata_dir: PathBuf,
 }
@ -235,6 +232,7 @@ impl System {
 	/// Create this node's membership manager
 	pub fn new(
 		network_key: NetworkKey,
+		background: Arc<BackgroundRunner>,
 		replication_mode: ReplicationMode,
 		config: &Config,
 	) -> Result<Arc<Self>, Error> {
@ -280,9 +278,6 @@ impl System {
 			cluster_layout_staging_hash: cluster_layout.staging_hash,
 		};

-		#[cfg(feature = "metrics")]
-		let metrics = SystemMetrics::new(replication_factor);
-
 		let ring = Ring::new(cluster_layout, replication_factor);
 		let (update_ring, ring) = watch::channel(Arc::new(ring));

@ -359,6 +354,7 @@ impl System {
 			rpc: RpcHelper::new(
 				netapp.id.into(),
 				fullmesh,
+				background.clone(),
 				ring.clone(),
 				config.rpc_timeout_msec.map(Duration::from_millis),
 			),
@ -373,11 +369,10 @@ impl System {
 			consul_discovery,
 			#[cfg(feature = "kubernetes-discovery")]
 			kubernetes_discovery: config.kubernetes_discovery.clone(),
-			#[cfg(feature = "metrics")]
-			metrics,

 			ring,
 			update_ring: Mutex::new(update_ring),
+			background,
 			metadata_dir: config.metadata_dir.clone(),
 		});
 		sys.system_endpoint.set_handler(sys.clone());
@ -449,14 +444,17 @@ impl System {
 				))
 			})?;
 		let mut errors = vec![];
-		for addr in addrs.iter() {
-			match self.netapp.clone().try_connect(*addr, pubkey).await {
+		for ip in addrs.iter() {
+			match self
+				.netapp
+				.clone()
+				.try_connect(*ip, pubkey)
+				.await
+				.err_context(CONNECT_ERROR_MESSAGE)
+			{
 				Ok(()) => return Ok(()),
 				Err(e) => {
-					errors.push((
-						*addr,
-						Error::Message(connect_error_message(*addr, pubkey, e)),
-					));
+					errors.push((*ip, e));
 				}
 			}
 		}
@ -531,61 +529,56 @@ impl System {
 	// ---- INTERNALS ----

 	#[cfg(feature = "consul-discovery")]
-	async fn advertise_to_consul(self: Arc<Self>) {
+	async fn advertise_to_consul(self: Arc<Self>) -> Result<(), Error> {
 		let c = match &self.consul_discovery {
 			Some(c) => c,
-			_ => return,
+			_ => return Ok(()),
 		};

 		let rpc_public_addr = match self.rpc_public_addr {
 			Some(addr) => addr,
 			None => {
 				warn!("Not advertising to Consul because rpc_public_addr is not defined in config file and could not be autodetected.");
-				return;
+				return Ok(());
 			}
 		};

-		if let Err(e) = c
-			.publish_consul_service(
+		c.publish_consul_service(
 			self.netapp.id,
 			&self.local_status.load_full().hostname,
 			rpc_public_addr,
 		)
 		.await
-		{
-			error!("Error while publishing Consul service: {}", e);
-		}
+		.err_context("Error while publishing Consul service")
 	}

 	#[cfg(feature = "kubernetes-discovery")]
-	async fn advertise_to_kubernetes(self: Arc<Self>) {
+	async fn advertise_to_kubernetes(self: Arc<Self>) -> Result<(), Error> {
 		let k = match &self.kubernetes_discovery {
 			Some(k) => k,
-			_ => return,
+			_ => return Ok(()),
 		};

 		let rpc_public_addr = match self.rpc_public_addr {
 			Some(addr) => addr,
 			None => {
 				warn!("Not advertising to Kubernetes because rpc_public_addr is not defined in config file and could not be autodetected.");
-				return;
+				return Ok(());
 			}
 		};

-		if let Err(e) = publish_kubernetes_node(
+		publish_kubernetes_node(
 			k,
 			self.netapp.id,
 			&self.local_status.load_full().hostname,
 			rpc_public_addr,
 		)
 		.await
-		{
-			error!("Error while publishing node to Kubernetes: {}", e);
-		}
+		.err_context("Error while publishing node to kubernetes")
 	}

 	/// Save network configuration to disc
-	async fn save_cluster_layout(&self) -> Result<(), Error> {
+	async fn save_cluster_layout(self: Arc<Self>) -> Result<(), Error> {
 		let ring: Arc<Ring> = self.ring.borrow().clone();
 		self.persist_cluster_layout
 			.save_async(&ring.layout)
@ -637,7 +630,11 @@ impl System {
 		if info.cluster_layout_version > local_info.cluster_layout_version
 			|| info.cluster_layout_staging_hash != local_info.cluster_layout_staging_hash
 		{
-			tokio::spawn(self.clone().pull_cluster_layout(from));
+			let self2 = self.clone();
+			self.background.spawn_cancellable(async move {
+				self2.pull_cluster_layout(from).await;
+				Ok(())
+			});
 		}

 		self.node_status
@ -679,21 +676,18 @@ impl System {
 			drop(update_ring);

 			let self2 = self.clone();
-			tokio::spawn(async move {
-				if let Err(e) = self2
+			self.background.spawn_cancellable(async move {
+				self2
 					.rpc
 					.broadcast(
 						&self2.system_endpoint,
 						SystemRpc::AdvertiseClusterLayout(layout),
 						RequestStrategy::with_priority(PRIO_HIGH),
 					)
-					.await
-				{
-					warn!("Error while broadcasting new cluster layout: {}", e);
-				}
+					.await?;
+				Ok(())
 			});
-
-			self.save_cluster_layout().await?;
+			self.background.spawn(self.clone().save_cluster_layout());
 		}

 		Ok(SystemRpc::Ok)
@ -740,7 +734,7 @@ impl System {

 				// Add peer list from list stored on disk
 				if let Ok(peers) = self.persist_peer_list.load_async().await {
-					ping_list.extend(peers.0.iter().map(|(id, addr)| ((*id).into(), *addr)))
+					ping_list.extend(peers.iter().map(|(id, addr)| ((*id).into(), *addr)))
 				}

 				// Fetch peer list from Consul
@ -779,12 +773,12 @@ impl System {
 				}

 				for (node_id, node_addr) in ping_list {
-					let self2 = self.clone();
-					tokio::spawn(async move {
-						if let Err(e) = self2.netapp.clone().try_connect(node_addr, node_id).await {
-							error!("{}", connect_error_message(node_addr, node_id, e));
-						}
-					});
+					tokio::spawn(
+						self.netapp
+							.clone()
+							.try_connect(node_addr, node_id)
+							.map(|r| r.err_context(CONNECT_ERROR_MESSAGE)),
+					);
 				}
 			}

@ -793,10 +787,11 @@ impl System {
 			}

 			#[cfg(feature = "consul-discovery")]
-			tokio::spawn(self.clone().advertise_to_consul());
+			self.background.spawn(self.clone().advertise_to_consul());

 			#[cfg(feature = "kubernetes-discovery")]
-			tokio::spawn(self.clone().advertise_to_kubernetes());
+			self.background
+				.spawn(self.clone().advertise_to_kubernetes());

 			let restart_at = tokio::time::sleep(DISCOVERY_INTERVAL);
 			select! {
@ -820,16 +815,12 @@ impl System {
 		// and append it to the list we are about to save,
 		// so that no peer ID gets lost in the process.
 		if let Ok(mut prev_peer_list) = self.persist_peer_list.load_async().await {
-			prev_peer_list
-				.0
-				.retain(|(id, _ip)| peer_list.iter().all(|(id2, _ip2)| id2 != id));
-			peer_list.extend(prev_peer_list.0);
+			prev_peer_list.retain(|(id, _ip)| peer_list.iter().all(|(id2, _ip2)| id2 != id));
+			peer_list.extend(prev_peer_list);
 		}

 		// Save new peer list to file
-		self.persist_peer_list
-			.save_async(&PeerList(peer_list))
-			.await
+		self.persist_peer_list.save_async(&peer_list).await
 	}

 	async fn pull_cluster_layout(self: Arc<Self>, peer: Uuid) {
@ -890,11 +881,3 @@ async fn resolve_peers(peers: &[String]) -> Vec<(NodeID, SocketAddr)> {

 	ret
 }
-
-fn connect_error_message(
-	addr: SocketAddr,
-	pubkey: ed25519::PublicKey,
-	e: netapp::error::Error,
-) -> String {
-	format!("Error establishing RPC connection to remote node: {}@{}.\nThis can happen if the remote node is not reachable on the network, but also if the two nodes are not configured with the same rpc_secret.\n{}", hex::encode(pubkey), addr, e)
-}
--- a/src/rpc/system_metrics.rs
+++ b/src/rpc/system_metrics.rs
@ -1,33 +0,0 @@
-use opentelemetry::{global, metrics::*, KeyValue};
-
-/// TableMetrics reference all counter used for metrics
-pub struct SystemMetrics {
-	pub(crate) _garage_build_info: ValueObserver<u64>,
-	pub(crate) _replication_factor: ValueObserver<u64>,
-}
-
-impl SystemMetrics {
-	pub fn new(replication_factor: usize) -> Self {
-		let meter = global::meter("garage_system");
-		Self {
-			_garage_build_info: meter
-				.u64_value_observer("garage_build_info", move |observer| {
-					observer.observe(
-						1,
-						&[KeyValue::new(
-							"version",
-							garage_util::version::garage_version(),
-						)],
-					)
-				})
-				.with_description("Garage build info")
-				.init(),
-			_replication_factor: meter
-				.u64_value_observer("garage_replication_factor", move |observer| {
-					observer.observe(replication_factor as u64, &[])
-				})
-				.with_description("Garage replication factor setting")
-				.init(),
-		}
-	}
-}
--- a/src/table/Cargo.toml
+++ b/src/table/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_table"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,20 +14,20 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_db = { version = "0.8.1", path = "../db" }
-garage_rpc = { version = "0.8.1", path = "../rpc" }
-garage_util = { version = "0.8.1", path = "../util" }
+garage_db = { version = "0.8.0", path = "../db" }
+garage_rpc = { version = "0.8.0", path = "../rpc" }
+garage_util = { version = "0.8.0", path = "../util" }

 opentelemetry = "0.17"

 async-trait = "0.1.7"
-arc-swap = "1.0"
 bytes = "1.0"
 hex = "0.4"
 hexdump = "0.1"
 tracing = "0.1.30"
 rand = "0.8"

+rmp-serde = "0.15"
 serde = { version = "1.0", default-features = false, features = ["derive", "rc"] }
 serde_bytes = "0.11"

--- a/src/table/data.rs
+++ b/src/table/data.rs
@ -10,7 +10,6 @@ use garage_db::counted_tree_hack::CountedTree;

 use garage_util::data::*;
 use garage_util::error::*;
-use garage_util::migrate::Migrate;

 use garage_rpc::system::System;

@ -32,16 +31,16 @@ pub struct TableData<F: TableSchema, R: TableReplication> {
 	pub(crate) merkle_tree: db::Tree,
 	pub(crate) merkle_todo: db::Tree,
 	pub(crate) merkle_todo_notify: Notify,
-
-	pub(crate) insert_queue: db::Tree,
-	pub(crate) insert_queue_notify: Notify,
-
 	pub(crate) gc_todo: CountedTree,

 	pub(crate) metrics: TableMetrics,
 }

-impl<F: TableSchema, R: TableReplication> TableData<F, R> {
+impl<F, R> TableData<F, R>
+where
+	F: TableSchema,
+	R: TableReplication,
+{
 	pub fn new(system: Arc<System>, instance: F, replication: R, db: &db::Db) -> Arc<Self> {
 		let store = db
 			.open_tree(&format!("{}:table", F::TABLE_NAME))
@ -54,22 +53,12 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 			.open_tree(&format!("{}:merkle_todo", F::TABLE_NAME))
 			.expect("Unable to open DB Merkle TODO tree");

-		let insert_queue = db
-			.open_tree(&format!("{}:insert_queue", F::TABLE_NAME))
-			.expect("Unable to open insert queue DB tree");
-
 		let gc_todo = db
 			.open_tree(&format!("{}:gc_todo_v2", F::TABLE_NAME))
-			.expect("Unable to open GC DB tree");
+			.expect("Unable to open DB tree");
 		let gc_todo = CountedTree::new(gc_todo).expect("Cannot count gc_todo_v2");

-		let metrics = TableMetrics::new(
-			F::TABLE_NAME,
-			store.clone(),
-			merkle_tree.clone(),
-			merkle_todo.clone(),
-			gc_todo.clone(),
-		);
+		let metrics = TableMetrics::new(F::TABLE_NAME, merkle_todo.clone(), gc_todo.clone());

 		Arc::new(Self {
 			system,
@ -79,8 +68,6 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 			merkle_tree,
 			merkle_todo,
 			merkle_todo_notify: Notify::new(),
-			insert_queue,
-			insert_queue_notify: Notify::new(),
 			gc_todo,
 			metrics,
 		})
@ -180,8 +167,9 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {

 	pub(crate) fn update_entry(&self, update_bytes: &[u8]) -> Result<(), Error> {
 		let update = self.decode_entry(update_bytes)?;
+		let tree_key = self.tree_key(update.partition_key(), update.sort_key());

-		self.update_entry_with(update.partition_key(), update.sort_key(), |ent| match ent {
+		self.update_entry_with(&tree_key[..], |ent| match ent {
 			Some(mut ent) => {
 				ent.merge(&update);
 				ent
@ -193,14 +181,11 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {

 	pub fn update_entry_with(
 		&self,
-		partition_key: &F::P,
-		sort_key: &F::S,
+		tree_key: &[u8],
 		f: impl Fn(Option<F::E>) -> F::E,
 	) -> Result<Option<F::E>, Error> {
-		let tree_key = self.tree_key(partition_key, sort_key);
-
 		let changed = self.store.db().transaction(|mut tx| {
-			let (old_entry, old_bytes, new_entry) = match tx.get(&self.store, &tree_key)? {
+			let (old_entry, old_bytes, new_entry) = match tx.get(&self.store, tree_key)? {
 				Some(old_bytes) => {
 					let old_entry = self.decode_entry(&old_bytes).map_err(db::TxError::Abort)?;
 					let new_entry = f(Some(old_entry.clone()));
@ -209,24 +194,23 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 				None => (None, None, f(None)),
 			};

-			// Changed can be true in two scenarios
-			// Scenario 1: the actual represented value changed,
-			//   so of course the messagepack encoding changed as well
+			// Scenario 1: the value changed, so of course there is a change
+			let value_changed = Some(&new_entry) != old_entry.as_ref();
+
 			// Scenario 2: the value didn't change but due to a migration in the
-			//   data format, the messagepack encoding changed. In this case,
-			//   we also have to write the migrated value in the table and update
+			// data format, the messagepack encoding changed. In this case
+			// we have to write the migrated value in the table and update
 			// the associated Merkle tree entry.
-			let new_bytes = new_entry
-				.encode()
+			let new_bytes = rmp_to_vec_all_named(&new_entry)
 				.map_err(Error::RmpEncode)
 				.map_err(db::TxError::Abort)?;
-			let changed = Some(&new_bytes[..]) != old_bytes.as_deref();
+			let encoding_changed = Some(&new_bytes[..]) != old_bytes.as_ref().map(|x| &x[..]);
 			drop(old_bytes);

-			if changed {
-				let new_bytes_hash = blake2sum(&new_bytes);
-				tx.insert(&self.merkle_todo, &tree_key, new_bytes_hash.as_slice())?;
-				tx.insert(&self.store, &tree_key, new_bytes)?;
+			if value_changed || encoding_changed {
+				let new_bytes_hash = blake2sum(&new_bytes[..]);
+				tx.insert(&self.merkle_todo, tree_key, new_bytes_hash.as_slice())?;
+				tx.insert(&self.store, tree_key, new_bytes)?;

 				self.instance
 					.updated(&mut tx, old_entry.as_ref(), Some(&new_entry))?;
@ -252,7 +236,7 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 				let pk_hash = Hash::try_from(&tree_key[..32]).unwrap();
 				let nodes = self.replication.write_nodes(&pk_hash);
 				if nodes.first() == Some(&self.system.id) {
-					GcTodoEntry::new(tree_key, new_bytes_hash).save(&self.gc_todo)?;
+					GcTodoEntry::new(tree_key.to_vec(), new_bytes_hash).save(&self.gc_todo)?;
 				}
 			}

@ -268,11 +252,10 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 			.db()
 			.transaction(|mut tx| match tx.get(&self.store, k)? {
 				Some(cur_v) if cur_v == v => {
-					let old_entry = self.decode_entry(v).map_err(db::TxError::Abort)?;
-
 					tx.remove(&self.store, k)?;
 					tx.insert(&self.merkle_todo, k, vec![])?;

+					let old_entry = self.decode_entry(v).map_err(db::TxError::Abort)?;
 					self.instance.updated(&mut tx, Some(&old_entry), None)?;
 					Ok(true)
 				}
@ -296,11 +279,10 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 			.db()
 			.transaction(|mut tx| match tx.get(&self.store, k)? {
 				Some(cur_v) if blake2sum(&cur_v[..]) == vhash => {
-					let old_entry = self.decode_entry(&cur_v[..]).map_err(db::TxError::Abort)?;
-
 					tx.remove(&self.store, k)?;
 					tx.insert(&self.merkle_todo, k, vec![])?;

+					let old_entry = self.decode_entry(&cur_v[..]).map_err(db::TxError::Abort)?;
 					self.instance.updated(&mut tx, Some(&old_entry), None)?;
 					Ok(true)
 				}
@ -314,32 +296,6 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 		Ok(removed)
 	}

-	// ---- Insert queue functions ----
-
-	pub(crate) fn queue_insert(
-		&self,
-		tx: &mut db::Transaction,
-		ins: &F::E,
-	) -> db::TxResult<(), Error> {
-		let tree_key = self.tree_key(ins.partition_key(), ins.sort_key());
-
-		let new_entry = match tx.get(&self.insert_queue, &tree_key)? {
-			Some(old_v) => {
-				let mut entry = self.decode_entry(&old_v).map_err(db::TxError::Abort)?;
-				entry.merge(ins);
-				entry.encode()
-			}
-			None => ins.encode(),
-		};
-		let new_entry = new_entry
-			.map_err(Error::RmpEncode)
-			.map_err(db::TxError::Abort)?;
-		tx.insert(&self.insert_queue, &tree_key, new_entry)?;
-		self.insert_queue_notify.notify_one();
-
-		Ok(())
-	}
-
 	// ---- Utility functions ----

 	pub fn tree_key(&self, p: &F::P, s: &F::S) -> Vec<u8> {
@ -349,18 +305,18 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> {
 	}

 	pub fn decode_entry(&self, bytes: &[u8]) -> Result<F::E, Error> {
-		match F::E::decode(bytes) {
+		match rmp_serde::decode::from_read_ref::<_, F::E>(bytes) {
+			Ok(x) => Ok(x),
+			Err(e) => match F::try_migrate(bytes) {
 				Some(x) => Ok(x),
 				None => {
-				error!("Unable to decode entry of {}", F::TABLE_NAME);
+					warn!("Unable to decode entry of {}: {}", F::TABLE_NAME, e);
 					for line in hexdump::hexdump_iter(bytes) {
 						debug!("{}", line);
 					}
-				Err(Error::Message(format!(
-					"Unable to decode entry of {}",
-					F::TABLE_NAME
-				)))
+					Err(e.into())
 				}
+			},
 		}
 	}

--- a/src/table/gc.rs
+++ b/src/table/gc.rs
@ -31,7 +31,7 @@ const TABLE_GC_BATCH_SIZE: usize = 1024;
 // and the moment the garbage collection actually happens)
 const TABLE_GC_DELAY: Duration = Duration::from_secs(24 * 3600);

-pub(crate) struct TableGc<F: TableSchema, R: TableReplication> {
+pub(crate) struct TableGc<F: TableSchema + 'static, R: TableReplication + 'static> {
 	system: Arc<System>,
 	data: Arc<TableData<F, R>>,

@ -49,24 +49,27 @@ impl Rpc for GcRpc {
 	type Response = Result<GcRpc, Error>;
 }

-impl<F: TableSchema, R: TableReplication> TableGc<F, R> {
-	pub(crate) fn new(system: Arc<System>, data: Arc<TableData<F, R>>) -> Arc<Self> {
+impl<F, R> TableGc<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
+	pub(crate) fn launch(system: Arc<System>, data: Arc<TableData<F, R>>) -> Arc<Self> {
 		let endpoint = system
 			.netapp
 			.endpoint(format!("garage_table/gc.rs/Rpc:{}", F::TABLE_NAME));

 		let gc = Arc::new(Self {
-			system,
+			system: system.clone(),
 			data,
 			endpoint,
 		});
+
 		gc.endpoint.set_handler(gc.clone());

-		gc
-	}
+		system.background.spawn_worker(GcWorker::new(gc.clone()));

-	pub(crate) fn spawn_workers(self: &Arc<Self>, bg: &BackgroundRunner) {
-		bg.spawn_worker(GcWorker::new(self.clone()));
+		gc
 	}

 	async fn gc_loop_iter(&self) -> Result<Option<Duration>, Error> {
@ -273,7 +276,11 @@ impl<F: TableSchema, R: TableReplication> TableGc<F, R> {
 }

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> EndpointHandler<GcRpc> for TableGc<F, R> {
+impl<F, R> EndpointHandler<GcRpc> for TableGc<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	async fn handle(self: &Arc<Self>, message: &GcRpc, _from: NodeID) -> Result<GcRpc, Error> {
 		match message {
 			GcRpc::Update(items) => {
@ -291,12 +298,20 @@ impl<F: TableSchema, R: TableReplication> EndpointHandler<GcRpc> for TableGc<F,
 	}
 }

-struct GcWorker<F: TableSchema, R: TableReplication> {
+struct GcWorker<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	gc: Arc<TableGc<F, R>>,
 	wait_delay: Duration,
 }

-impl<F: TableSchema, R: TableReplication> GcWorker<F, R> {
+impl<F, R> GcWorker<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	fn new(gc: Arc<TableGc<F, R>>) -> Self {
 		Self {
 			gc,
@ -306,15 +321,21 @@ impl<F: TableSchema, R: TableReplication> GcWorker<F, R> {
 }

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> Worker for GcWorker<F, R> {
+impl<F, R> Worker for GcWorker<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	fn name(&self) -> String {
 		format!("{} GC", F::TABLE_NAME)
 	}

-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			queue_length: Some(self.gc.data.gc_todo_len().unwrap_or(0) as u64),
-			..Default::default()
+	fn info(&self) -> Option<String> {
+		let l = self.gc.data.gc_todo_len().unwrap_or(0);
+		if l > 0 {
+			Some(format!("{} items in queue", l))
+		} else {
+			None
 		}
 	}

@ -328,7 +349,10 @@ impl<F: TableSchema, R: TableReplication> Worker for GcWorker<F, R> {
 		}
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, must_exit: &watch::Receiver<bool>) -> WorkerState {
+		if *must_exit.borrow() {
+			return WorkerState::Done;
+		}
 		tokio::time::sleep(self.wait_delay).await;
 		WorkerState::Busy
 	}
--- a/src/table/lib.rs
+++ b/src/table/lib.rs
@ -4,18 +4,16 @@
 #[macro_use]
 extern crate tracing;

+mod metrics;
 pub mod schema;
 pub mod util;

 pub mod data;
-pub mod replication;
-pub mod table;
-
 mod gc;
 mod merkle;
-mod metrics;
-mod queue;
+pub mod replication;
 mod sync;
+pub mod table;

 pub use schema::*;
 pub use table::*;
--- a/src/table/merkle.rs
+++ b/src/table/merkle.rs
@ -3,14 +3,12 @@ use std::time::Duration;

 use async_trait::async_trait;
 use serde::{Deserialize, Serialize};
-use tokio::select;
 use tokio::sync::watch;

 use garage_db as db;

 use garage_util::background::*;
 use garage_util::data::*;
-use garage_util::encode::{nonversioned_decode, nonversioned_encode};
 use garage_util::error::Error;

 use garage_rpc::ring::*;
@ -66,18 +64,22 @@ pub enum MerkleNode {
 	Leaf(Vec<u8>, Hash),
 }

-impl<F: TableSchema, R: TableReplication> MerkleUpdater<F, R> {
-	pub(crate) fn new(data: Arc<TableData<F, R>>) -> Arc<Self> {
-		let empty_node_hash = blake2sum(&nonversioned_encode(&MerkleNode::Empty).unwrap()[..]);
+impl<F, R> MerkleUpdater<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
+	pub(crate) fn launch(background: &BackgroundRunner, data: Arc<TableData<F, R>>) -> Arc<Self> {
+		let empty_node_hash = blake2sum(&rmp_to_vec_all_named(&MerkleNode::Empty).unwrap()[..]);

-		Arc::new(Self {
+		let ret = Arc::new(Self {
 			data,
 			empty_node_hash,
-		})
-	}
+		});

-	pub(crate) fn spawn_workers(self: &Arc<Self>, background: &BackgroundRunner) {
-		background.spawn_worker(MerkleWorker(self.clone()));
+		background.spawn_worker(MerkleWorker(ret.clone()));
+
+		ret
 	}

 	fn updater_loop_iter(&self) -> Result<WorkerState, Error> {
@ -274,7 +276,7 @@ impl<F: TableSchema, R: TableReplication> MerkleUpdater<F, R> {
 			tx.remove(&self.data.merkle_tree, k.encode())?;
 			Ok(self.empty_node_hash)
 		} else {
-			let vby = nonversioned_encode(v).map_err(|e| db::TxError::Abort(e.into()))?;
+			let vby = rmp_to_vec_all_named(v).map_err(|e| db::TxError::Abort(e.into()))?;
 			let rethash = blake2sum(&vby[..]);
 			tx.insert(&self.data.merkle_tree, k.encode(), vby)?;
 			Ok(rethash)
@ -291,27 +293,32 @@ impl<F: TableSchema, R: TableReplication> MerkleUpdater<F, R> {
 		Ok(self.data.merkle_tree.len()?)
 	}

-	pub fn merkle_tree_fast_len(&self) -> Result<Option<usize>, Error> {
-		Ok(self.data.merkle_tree.fast_len()?)
-	}
-
 	pub fn todo_len(&self) -> Result<usize, Error> {
 		Ok(self.data.merkle_todo.len()?)
 	}
 }

-struct MerkleWorker<F: TableSchema, R: TableReplication>(Arc<MerkleUpdater<F, R>>);
+struct MerkleWorker<F, R>(Arc<MerkleUpdater<F, R>>)
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static;

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> Worker for MerkleWorker<F, R> {
+impl<F, R> Worker for MerkleWorker<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	fn name(&self) -> String {
-		format!("{} Merkle", F::TABLE_NAME)
+		format!("{} Merkle tree updater", F::TABLE_NAME)
 	}

-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			queue_length: Some(self.0.todo_len().unwrap_or(0) as u64),
-			..Default::default()
+	fn info(&self) -> Option<String> {
+		let l = self.0.todo_len().unwrap_or(0);
+		if l > 0 {
+			Some(format!("{} items in queue", l))
+		} else {
+			None
 		}
 	}

@ -330,11 +337,11 @@ impl<F: TableSchema, R: TableReplication> Worker for MerkleWorker<F, R> {
 		.unwrap()
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
-		select! {
-			_ = tokio::time::sleep(Duration::from_secs(60)) => (),
-			_ = self.0.data.merkle_todo_notify.notified() => (),
+	async fn wait_for_work(&mut self, must_exit: &watch::Receiver<bool>) -> WorkerState {
+		if *must_exit.borrow() {
+			return WorkerState::Done;
 		}
+		tokio::time::sleep(Duration::from_secs(10)).await;
 		WorkerState::Busy
 	}
 }
@ -365,7 +372,7 @@ impl MerkleNode {
 	fn decode_opt(ent: &Option<db::Value>) -> Result<Self, Error> {
 		match ent {
 			None => Ok(MerkleNode::Empty),
-			Some(v) => Ok(nonversioned_decode::<MerkleNode>(&v[..])?),
+			Some(v) => Ok(rmp_serde::decode::from_read_ref::<_, MerkleNode>(&v[..])?),
 		}
 	}

--- a/src/table/metrics.rs
+++ b/src/table/metrics.rs
@ -5,8 +5,6 @@ use garage_db::counted_tree_hack::CountedTree;

 /// TableMetrics reference all counter used for metrics
 pub struct TableMetrics {
-	pub(crate) _table_size: ValueObserver<u64>,
-	pub(crate) _merkle_tree_size: ValueObserver<u64>,
 	pub(crate) _merkle_todo_len: ValueObserver<u64>,
 	pub(crate) _gc_todo_len: ValueObserver<u64>,

@ -22,43 +20,9 @@ pub struct TableMetrics {
 	pub(crate) sync_items_received: Counter<u64>,
 }
 impl TableMetrics {
-	pub fn new(
-		table_name: &'static str,
-		store: db::Tree,
-		merkle_tree: db::Tree,
-		merkle_todo: db::Tree,
-		gc_todo: CountedTree,
-	) -> Self {
+	pub fn new(table_name: &'static str, merkle_todo: db::Tree, gc_todo: CountedTree) -> Self {
 		let meter = global::meter(table_name);
 		TableMetrics {
-			_table_size: meter
-				.u64_value_observer(
-					"table.size",
-					move |observer| {
-						if let Ok(Some(v)) = store.fast_len() {
-							observer.observe(
-								v as u64,
-								&[KeyValue::new("table_name", table_name)],
-							);
-						}
-					},
-				)
-				.with_description("Number of items in table")
-				.init(),
-			_merkle_tree_size: meter
-				.u64_value_observer(
-					"table.merkle_tree_size",
-					move |observer| {
-						if let Ok(Some(v)) = merkle_tree.fast_len() {
-							observer.observe(
-								v as u64,
-								&[KeyValue::new("table_name", table_name)],
-							);
-						}
-					},
-				)
-				.with_description("Number of nodes in table's Merkle tree")
-				.init(),
 			_merkle_todo_len: meter
 				.u64_value_observer(
 					"table.merkle_updater_todo_queue_length",
--- a/src/table/queue.rs
+++ b/src/table/queue.rs
@ -1,77 +0,0 @@
-use std::sync::Arc;
-use std::time::Duration;
-
-use async_trait::async_trait;
-use tokio::select;
-use tokio::sync::watch;
-
-use garage_util::background::*;
-use garage_util::error::Error;
-
-use crate::replication::*;
-use crate::schema::*;
-use crate::table::*;
-
-const BATCH_SIZE: usize = 100;
-
-pub(crate) struct InsertQueueWorker<F, R>(pub(crate) Arc<Table<F, R>>)
-where
-	F: TableSchema,
-	R: TableReplication;
-
-#[async_trait]
-impl<F: TableSchema, R: TableReplication> Worker for InsertQueueWorker<F, R> {
-	fn name(&self) -> String {
-		format!("{} queue", F::TABLE_NAME)
-	}
-
-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			queue_length: Some(self.0.data.insert_queue.len().unwrap_or(0) as u64),
-			..Default::default()
-		}
-	}
-
-	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
-		let mut kv_pairs = vec![];
-		let mut values = vec![];
-
-		for entry_kv in self.0.data.insert_queue.iter()? {
-			let (k, v) = entry_kv?;
-
-			values.push(self.0.data.decode_entry(&v)?);
-			kv_pairs.push((k, v));
-
-			if kv_pairs.len() > BATCH_SIZE {
-				break;
-			}
-		}
-
-		if kv_pairs.is_empty() {
-			return Ok(WorkerState::Idle);
-		}
-
-		self.0.insert_many(values).await?;
-
-		self.0.data.insert_queue.db().transaction(|mut tx| {
-			for (k, v) in kv_pairs.iter() {
-				if let Some(v2) = tx.get(&self.0.data.insert_queue, k)? {
-					if &v2 == v {
-						tx.remove(&self.0.data.insert_queue, k)?;
-					}
-				}
-			}
-			Ok(())
-		})?;
-
-		Ok(WorkerState::Busy)
-	}
-
-	async fn wait_for_work(&mut self) -> WorkerState {
-		select! {
-			_ = tokio::time::sleep(Duration::from_secs(600)) => (),
-			_ = self.0.data.insert_queue_notify.notified() => (),
-		}
-		WorkerState::Busy
-	}
-}
--- a/src/table/replication/parameters.rs
+++ b/src/table/replication/parameters.rs
@ -2,7 +2,7 @@ use garage_rpc::ring::*;
 use garage_util::data::*;

 /// Trait to describe how a table shall be replicated
-pub trait TableReplication: Send + Sync + 'static {
+pub trait TableReplication: Send + Sync {
 	// See examples in table_sharded.rs and table_fullcopy.rs
 	// To understand various replication methods

--- a/src/table/schema.rs
+++ b/src/table/schema.rs
@ -2,14 +2,11 @@ use serde::{Deserialize, Serialize};

 use garage_db as db;
 use garage_util::data::*;
-use garage_util::migrate::Migrate;

 use crate::crdt::Crdt;

 /// Trait for field used to partition data
-pub trait PartitionKey:
-	Clone + PartialEq + Serialize + for<'de> Deserialize<'de> + Send + Sync + 'static
-{
+pub trait PartitionKey {
 	/// Get the key used to partition
 	fn hash(&self) -> Hash;
 }
@ -30,7 +27,7 @@ impl PartitionKey for FixedBytes32 {
 }

 /// Trait for field used to sort data
-pub trait SortKey: Clone + Serialize + for<'de> Deserialize<'de> + Send + Sync + 'static {
+pub trait SortKey {
 	/// Get the key used to sort
 	fn sort_key(&self) -> &[u8];
 }
@ -49,7 +46,7 @@ impl SortKey for FixedBytes32 {

 /// Trait for an entry in a table. It must be sortable and partitionnable.
 pub trait Entry<P: PartitionKey, S: SortKey>:
-	Crdt + PartialEq + Clone + Migrate + Send + Sync + 'static
+	Crdt + PartialEq + Clone + Serialize + for<'de> Deserialize<'de> + Send + Sync
 {
 	/// Get the key used to partition
 	fn partition_key(&self) -> &P;
@ -68,16 +65,23 @@ pub trait TableSchema: Send + Sync + 'static {
 	const TABLE_NAME: &'static str;

 	/// The partition key used in that table
-	type P: PartitionKey;
+	type P: PartitionKey + Clone + PartialEq + Serialize + for<'de> Deserialize<'de> + Send + Sync;
 	/// The sort key used int that table
-	type S: SortKey;
+	type S: SortKey + Clone + Serialize + for<'de> Deserialize<'de> + Send + Sync;

 	/// They type for an entry in that table
 	type E: Entry<Self::P, Self::S>;

 	/// The type for a filter that can be applied to select entries
 	/// (e.g. filter out deleted entries)
-	type Filter: Clone + Serialize + for<'de> Deserialize<'de> + Send + Sync + 'static;
+	type Filter: Clone + Serialize + for<'de> Deserialize<'de> + Send + Sync;
+
+	// Action to take if not able to decode current version:
+	// try loading from an older version
+	/// Try migrating an entry from an older version
+	fn try_migrate(_bytes: &[u8]) -> Option<Self::E> {
+		None
+	}

 	/// Actions triggered by data changing in a table. If such actions
 	/// include updates to the local database that should be applied
--- a/src/table/sync.rs
+++ b/src/table/sync.rs
@ -2,7 +2,6 @@ use std::collections::VecDeque;
 use std::sync::Arc;
 use std::time::{Duration, Instant};

-use arc_swap::ArcSwapOption;
 use async_trait::async_trait;
 use futures_util::stream::*;
 use opentelemetry::KeyValue;
@ -14,8 +13,7 @@ use tokio::sync::{mpsc, watch};

 use garage_util::background::*;
 use garage_util::data::*;
-use garage_util::encode::{debug_serialize, nonversioned_encode};
-use garage_util::error::{Error, OkOrMessage};
+use garage_util::error::Error;

 use garage_rpc::ring::*;
 use garage_rpc::system::System;
@ -29,12 +27,12 @@ use crate::*;
 // Do anti-entropy every 10 minutes
 const ANTI_ENTROPY_INTERVAL: Duration = Duration::from_secs(10 * 60);

-pub struct TableSyncer<F: TableSchema, R: TableReplication> {
+pub struct TableSyncer<F: TableSchema + 'static, R: TableReplication + 'static> {
 	system: Arc<System>,
 	data: Arc<TableData<F, R>>,
 	merkle: Arc<MerkleUpdater<F, R>>,

-	add_full_sync_tx: ArcSwapOption<mpsc::UnboundedSender<()>>,
+	add_full_sync_tx: mpsc::UnboundedSender<()>,
 	endpoint: Arc<Endpoint<SyncRpc, Self>>,
 }

@ -62,8 +60,12 @@ struct TodoPartition {
 	retain: bool,
 }

-impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> {
-	pub(crate) fn new(
+impl<F, R> TableSyncer<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
+	pub(crate) fn launch(
 		system: Arc<System>,
 		data: Arc<TableData<F, R>>,
 		merkle: Arc<MerkleUpdater<F, R>>,
@ -72,40 +74,34 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> {
 			.netapp
 			.endpoint(format!("garage_table/sync.rs/Rpc:{}", F::TABLE_NAME));

+		let (add_full_sync_tx, add_full_sync_rx) = mpsc::unbounded_channel();
+
 		let syncer = Arc::new(Self {
-			system,
+			system: system.clone(),
 			data,
 			merkle,
-			add_full_sync_tx: ArcSwapOption::new(None),
+			add_full_sync_tx,
 			endpoint,
 		});
+
 		syncer.endpoint.set_handler(syncer.clone());

-		syncer
-	}
-
-	pub(crate) fn spawn_workers(self: &Arc<Self>, bg: &BackgroundRunner) {
-		let (add_full_sync_tx, add_full_sync_rx) = mpsc::unbounded_channel();
-		self.add_full_sync_tx
-			.store(Some(Arc::new(add_full_sync_tx)));
-
-		bg.spawn_worker(SyncWorker {
-			syncer: self.clone(),
-			ring_recv: self.system.ring.clone(),
-			ring: self.system.ring.borrow().clone(),
+		system.background.spawn_worker(SyncWorker {
+			syncer: syncer.clone(),
+			ring_recv: system.ring.clone(),
+			ring: system.ring.borrow().clone(),
 			add_full_sync_rx,
 			todo: vec![],
 			next_full_sync: Instant::now() + Duration::from_secs(20),
 		});
+
+		syncer
 	}

-	pub fn add_full_sync(&self) -> Result<(), Error> {
-		let tx = self.add_full_sync_tx.load();
-		let tx = tx
-			.as_ref()
-			.ok_or_message("table sync worker is not running")?;
-		tx.send(()).ok_or_message("send error")?;
-		Ok(())
+	pub fn add_full_sync(&self) {
+		if self.add_full_sync_tx.send(()).is_err() {
+			error!("({}) Could not add full sync", F::TABLE_NAME);
+		}
 	}

 	// ----
@ -299,7 +295,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> {
 			);
 			return Ok(());
 		}
-		let root_ck_hash = hash_of_merkle_node(&root_ck)?;
+		let root_ck_hash = hash_of::<MerkleNode>(&root_ck)?;

 		// Check if they have the same root checksum
 		// If so, do nothing.
@ -456,12 +452,16 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> {
 // ======= SYNCHRONIZATION PROCEDURE -- RECEIVER SIDE ======

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> EndpointHandler<SyncRpc> for TableSyncer<F, R> {
+impl<F, R> EndpointHandler<SyncRpc> for TableSyncer<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	async fn handle(self: &Arc<Self>, message: &SyncRpc, from: NodeID) -> Result<SyncRpc, Error> {
 		match message {
 			SyncRpc::RootCkHash(range, h) => {
 				let (_root_ck_key, root_ck) = self.get_root_ck(*range)?;
-				let hash = hash_of_merkle_node(&root_ck)?;
+				let hash = hash_of::<MerkleNode>(&root_ck)?;
 				Ok(SyncRpc::RootCkDifferent(hash != *h))
 			}
 			SyncRpc::GetNode(k) => {
@ -490,7 +490,7 @@ impl<F: TableSchema, R: TableReplication> EndpointHandler<SyncRpc> for TableSync

 // -------- Sync Worker ---------

-struct SyncWorker<F: TableSchema, R: TableReplication> {
+struct SyncWorker<F: TableSchema + 'static, R: TableReplication + 'static> {
 	syncer: Arc<TableSyncer<F, R>>,
 	ring_recv: watch::Receiver<Arc<Ring>>,
 	ring: Arc<Ring>,
@ -499,7 +499,7 @@ struct SyncWorker<F: TableSchema, R: TableReplication> {
 	next_full_sync: Instant,
 }

-impl<F: TableSchema, R: TableReplication> SyncWorker<F, R> {
+impl<F: TableSchema + 'static, R: TableReplication + 'static> SyncWorker<F, R> {
 	fn add_full_sync(&mut self) {
 		let system = &self.syncer.system;
 		let data = &self.syncer.data;
@ -565,15 +565,17 @@ impl<F: TableSchema, R: TableReplication> SyncWorker<F, R> {
 }

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> Worker for SyncWorker<F, R> {
+impl<F: TableSchema + 'static, R: TableReplication + 'static> Worker for SyncWorker<F, R> {
 	fn name(&self) -> String {
 		format!("{} sync", F::TABLE_NAME)
 	}

-	fn status(&self) -> WorkerStatus {
-		WorkerStatus {
-			queue_length: Some(self.todo.len() as u64),
-			..Default::default()
+	fn info(&self) -> Option<String> {
+		let l = self.todo.len();
+		if l > 0 {
+			Some(format!("{} partitions remaining", l))
+		} else {
+			None
 		}
 	}

@ -586,7 +588,10 @@ impl<F: TableSchema, R: TableReplication> Worker for SyncWorker<F, R> {
 		}
 	}

-	async fn wait_for_work(&mut self) -> WorkerState {
+	async fn wait_for_work(&mut self, must_exit: &watch::Receiver<bool>) -> WorkerState {
+		if *must_exit.borrow() {
+			return WorkerState::Done;
+		}
 		select! {
 			s = self.add_full_sync_rx.recv() => {
 				if let Some(()) = s {
@ -615,8 +620,8 @@ impl<F: TableSchema, R: TableReplication> Worker for SyncWorker<F, R> {

 // ---- UTIL ----

-fn hash_of_merkle_node(x: &MerkleNode) -> Result<Hash, Error> {
-	Ok(blake2sum(&nonversioned_encode(x)?[..]))
+fn hash_of<T: Serialize>(x: &T) -> Result<Hash, Error> {
+	Ok(blake2sum(&rmp_to_vec_all_named(x)?[..]))
 }

 fn join_ordered<'a, K: Ord + Eq, V1, V2>(
--- a/src/table/table.rs
+++ b/src/table/table.rs
@ -14,11 +14,9 @@ use opentelemetry::{

 use garage_db as db;

-use garage_util::background::BackgroundRunner;
 use garage_util::data::*;
 use garage_util::error::Error;
 use garage_util::metrics::RecordDuration;
-use garage_util::migrate::Migrate;

 use garage_rpc::system::System;
 use garage_rpc::*;
@ -27,18 +25,16 @@ use crate::crdt::Crdt;
 use crate::data::*;
 use crate::gc::*;
 use crate::merkle::*;
-use crate::queue::InsertQueueWorker;
 use crate::replication::*;
 use crate::schema::*;
 use crate::sync::*;
 use crate::util::*;

-pub struct Table<F: TableSchema, R: TableReplication> {
+pub struct Table<F: TableSchema + 'static, R: TableReplication + 'static> {
 	pub system: Arc<System>,
 	pub data: Arc<TableData<F, R>>,
 	pub merkle_updater: Arc<MerkleUpdater<F, R>>,
 	pub syncer: Arc<TableSyncer<F, R>>,
-	gc: Arc<TableGc<F, R>>,
 	endpoint: Arc<Endpoint<TableRpc<F>, Self>>,
 }

@ -65,7 +61,11 @@ impl<F: TableSchema> Rpc for TableRpc<F> {
 	type Response = Result<TableRpc<F>, Error>;
 }

-impl<F: TableSchema, R: TableReplication> Table<F, R> {
+impl<F, R> Table<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	// =============== PUBLIC INTERFACE FUNCTIONS (new, insert, get, etc) ===============

 	pub fn new(instance: F, replication: R, system: Arc<System>, db: &db::Db) -> Arc<Self> {
@ -75,16 +75,15 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {

 		let data = TableData::new(system.clone(), instance, replication, db);

-		let merkle_updater = MerkleUpdater::new(data.clone());
+		let merkle_updater = MerkleUpdater::launch(&system.background, data.clone());

-		let syncer = TableSyncer::new(system.clone(), data.clone(), merkle_updater.clone());
-		let gc = TableGc::new(system.clone(), data.clone());
+		let syncer = TableSyncer::launch(system.clone(), data.clone(), merkle_updater.clone());
+		TableGc::launch(system.clone(), data.clone());

 		let table = Arc::new(Self {
 			system,
 			data,
 			merkle_updater,
-			gc,
 			syncer,
 			endpoint,
 		});
@ -94,13 +93,6 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 		table
 	}

-	pub fn spawn_workers(self: &Arc<Self>, bg: &BackgroundRunner) {
-		self.merkle_updater.spawn_workers(bg);
-		self.syncer.spawn_workers(bg);
-		self.gc.spawn_workers(bg);
-		bg.spawn_worker(InsertQueueWorker(self.clone()));
-	}
-
 	pub async fn insert(&self, e: &F::E) -> Result<(), Error> {
 		let tracer = opentelemetry::global::tracer("garage_table");
 		let span = tracer.start(format!("{} insert", F::TABLE_NAME));
@ -119,7 +111,7 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 		let hash = e.partition_key().hash();
 		let who = self.data.replication.write_nodes(&hash);

-		let e_enc = Arc::new(ByteBuf::from(e.encode()?));
+		let e_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(e)?));
 		let rpc = TableRpc::<F>::Update(vec![e_enc]);

 		self.system
@ -136,11 +128,6 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 		Ok(())
 	}

-	/// Insert item locally
-	pub fn queue_insert(&self, tx: &mut db::Transaction, e: &F::E) -> db::TxResult<(), Error> {
-		self.data.queue_insert(tx, e)
-	}
-
 	pub async fn insert_many<I, IE>(&self, entries: I) -> Result<(), Error>
 	where
 		I: IntoIterator<Item = IE> + Send + Sync,
@ -170,7 +157,7 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 			let entry = entry.borrow();
 			let hash = entry.partition_key().hash();
 			let who = self.data.replication.write_nodes(&hash);
-			let e_enc = Arc::new(ByteBuf::from(entry.encode()?));
+			let e_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(entry)?));
 			for node in who {
 				call_list.entry(node).or_default().push(e_enc.clone());
 			}
@ -272,11 +259,9 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 			if not_all_same {
 				let self2 = self.clone();
 				let ent2 = ret_entry.clone();
-				tokio::spawn(async move {
-					if let Err(e) = self2.repair_on_read(&who[..], ent2).await {
-						warn!("Error doing repair on read: {}", e);
-					}
-				});
+				self.system
+					.background
+					.spawn_cancellable(async move { self2.repair_on_read(&who[..], ent2).await });
 			}
 		}

@ -373,12 +358,11 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 				.into_iter()
 				.map(|k| ret.get(&k).unwrap().clone())
 				.collect::<Vec<_>>();
-			tokio::spawn(async move {
+			self.system.background.spawn_cancellable(async move {
 				for v in to_repair {
-					if let Err(e) = self2.repair_on_read(&who[..], v).await {
-						warn!("Error doing repair on read: {}", e);
-					}
+					self2.repair_on_read(&who[..], v).await?;
 				}
+				Ok(())
 			});
 		}

@ -409,7 +393,7 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 	// =============== UTILITY FUNCTION FOR CLIENT OPERATIONS ===============

 	async fn repair_on_read(&self, who: &[Uuid], what: F::E) -> Result<(), Error> {
-		let what_enc = Arc::new(ByteBuf::from(what.encode()?));
+		let what_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(&what)?));
 		self.system
 			.rpc
 			.try_call_many(
@ -424,7 +408,11 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 }

 #[async_trait]
-impl<F: TableSchema, R: TableReplication> EndpointHandler<TableRpc<F>> for Table<F, R> {
+impl<F, R> EndpointHandler<TableRpc<F>> for Table<F, R>
+where
+	F: TableSchema + 'static,
+	R: TableReplication + 'static,
+{
 	async fn handle(
 		self: &Arc<Self>,
 		msg: &TableRpc<F>,
--- a/src/table/util.rs
+++ b/src/table/util.rs
@ -49,9 +49,3 @@ impl EnumerationOrder {
 		}
 	}
 }
-
-impl Default for EnumerationOrder {
-	fn default() -> Self {
-		EnumerationOrder::Forward
-	}
-}
--- a/src/util/Cargo.toml
+++ b/src/util/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_util"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,7 +14,7 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_db = { version = "0.8.1", path = "../db" }
+garage_db = { version = "0.8.0", path = "../db" }

 arc-swap = "1.0"
 async-trait = "0.1"
@ -23,7 +23,6 @@ bytes = "1.0"
 digest = "0.10"
 err-derive = "0.3"
 git-version = "0.3.4"
-hexdump = "0.1"
 xxhash-rust = { version = "0.8", default-features = false, features = ["xxh3"] }
 hex = "0.4"
 lazy_static = "1.4"
@ -47,8 +46,6 @@ hyper = "0.14"

 opentelemetry = { version = "0.17", features = [ "rt-tokio", "metrics", "trace" ] }

-[dev-dependencies]
-mktemp = "0.4"

 [features]
 k2v = []
--- a/src/util/background/job_worker.rs
+++ b/src/util/background/job_worker.rs
@ -0,0 +1,48 @@
+//! Job worker: a generic worker that just processes incoming
+//! jobs one by one
+
+use std::sync::Arc;
+
+use async_trait::async_trait;
+use tokio::sync::{mpsc, Mutex};
+
+use crate::background::worker::*;
+use crate::background::*;
+
+pub(crate) struct JobWorker {
+	pub(crate) index: usize,
+	pub(crate) job_chan: Arc<Mutex<mpsc::UnboundedReceiver<(Job, bool)>>>,
+	pub(crate) next_job: Option<Job>,
+}
+
+#[async_trait]
+impl Worker for JobWorker {
+	fn name(&self) -> String {
+		format!("Job worker #{}", self.index)
+	}
+
+	async fn work(&mut self, _must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> {
+		match self.next_job.take() {
+			None => return Ok(WorkerState::Idle),
+			Some(job) => {
+				job.await?;
+				Ok(WorkerState::Busy)
+			}
+		}
+	}
+
+	async fn wait_for_work(&mut self, must_exit: &watch::Receiver<bool>) -> WorkerState {
+		loop {
+			match self.job_chan.lock().await.recv().await {
+				Some((job, cancellable)) => {
+					if cancellable && *must_exit.borrow() {
+						continue;
+					}
+					self.next_job = Some(job);
+					return WorkerState::Busy;
+				}
+				None => return WorkerState::Done,
+			}
+		}
+	}
+}
--- a/src/util/background/mod.rs
+++ b/src/util/background/mod.rs
@ -1,19 +1,27 @@
 //! Job runner for futures and async functions

-pub mod vars;
+pub mod job_worker;
 pub mod worker;

+use core::future::Future;
+
 use std::collections::HashMap;
+use std::pin::Pin;
 use std::sync::Arc;

 use serde::{Deserialize, Serialize};
-use tokio::sync::{mpsc, watch};
+use tokio::sync::{mpsc, watch, Mutex};

+use crate::error::Error;
 use worker::WorkerProcessor;
 pub use worker::{Worker, WorkerState};

+pub(crate) type JobOutput = Result<(), Error>;
+pub(crate) type Job = Pin<Box<dyn Future<Output = JobOutput> + Send>>;
+
 /// Job runner for futures and async functions
 pub struct BackgroundRunner {
+	send_job: mpsc::UnboundedSender<(Job, bool)>,
 	send_worker: mpsc::UnboundedSender<Box<dyn Worker>>,
 	worker_info: Arc<std::sync::Mutex<HashMap<usize, WorkerInfo>>>,
 }
@ -21,27 +29,19 @@ pub struct BackgroundRunner {
 #[derive(Clone, Serialize, Deserialize, Debug)]
 pub struct WorkerInfo {
 	pub name: String,
-	pub status: WorkerStatus,
+	pub info: Option<String>,
 	pub state: WorkerState,
 	pub errors: usize,
 	pub consecutive_errors: usize,
 	pub last_error: Option<(String, u64)>,
 }

-/// WorkerStatus is a struct returned by the worker with a bunch of canonical
-/// fields to indicate their status to CLI users. All fields are optional.
-#[derive(Clone, Serialize, Deserialize, Debug, Default)]
-pub struct WorkerStatus {
-	pub tranquility: Option<u32>,
-	pub progress: Option<String>,
-	pub queue_length: Option<u64>,
-	pub persistent_errors: Option<u64>,
-	pub freeform: Vec<String>,
-}
-
 impl BackgroundRunner {
 	/// Create a new BackgroundRunner
-	pub fn new(stop_signal: watch::Receiver<bool>) -> (Arc<Self>, tokio::task::JoinHandle<()>) {
+	pub fn new(
+		n_runners: usize,
+		stop_signal: watch::Receiver<bool>,
+	) -> (Arc<Self>, tokio::task::JoinHandle<()>) {
 		let (send_worker, worker_out) = mpsc::unbounded_channel::<Box<dyn Worker>>();

 		let worker_info = Arc::new(std::sync::Mutex::new(HashMap::new()));
@ -52,7 +52,24 @@ impl BackgroundRunner {
 			worker_processor.run().await;
 		});

+		let (send_job, queue_out) = mpsc::unbounded_channel();
+		let queue_out = Arc::new(Mutex::new(queue_out));
+
+		for i in 0..n_runners {
+			let queue_out = queue_out.clone();
+
+			send_worker
+				.send(Box::new(job_worker::JobWorker {
+					index: i,
+					job_chan: queue_out.clone(),
+					next_job: None,
+				}))
+				.ok()
+				.unwrap();
+		}
+
 		let bgrunner = Arc::new(Self {
+			send_job,
 			send_worker,
 			worker_info,
 		});
@ -63,6 +80,31 @@ impl BackgroundRunner {
 		self.worker_info.lock().unwrap().clone()
 	}

+	/// Spawn a task to be run in background
+	pub fn spawn<T>(&self, job: T)
+	where
+		T: Future<Output = JobOutput> + Send + 'static,
+	{
+		let boxed: Job = Box::pin(job);
+		self.send_job
+			.send((boxed, false))
+			.ok()
+			.expect("Could not put job in queue");
+	}
+
+	/// Spawn a task to be run in background. It may get discarded before running if spawned while
+	/// the runner is stopping
+	pub fn spawn_cancellable<T>(&self, job: T)
+	where
+		T: Future<Output = JobOutput> + Send + 'static,
+	{
+		let boxed: Job = Box::pin(job);
+		self.send_job
+			.send((boxed, true))
+			.ok()
+			.expect("Could not put job in queue");
+	}
+
 	pub fn spawn_worker<W>(&self, worker: W)
 	where
 		W: Worker + 'static,
--- a/src/util/background/vars.rs
+++ b/src/util/background/vars.rs
@ -1,113 +0,0 @@
-use std::collections::HashMap;
-use std::str::FromStr;
-
-use crate::error::{Error, OkOrMessage};
-use crate::migrate::Migrate;
-use crate::persister::PersisterShared;
-
-pub struct BgVars {
-	vars: HashMap<&'static str, Box<dyn BgVarTrait>>,
-}
-
-impl BgVars {
-	pub fn new() -> Self {
-		Self {
-			vars: HashMap::new(),
-		}
-	}
-
-	pub fn register_rw<V, T, GF, SF>(
-		&mut self,
-		p: &PersisterShared<V>,
-		name: &'static str,
-		get_fn: GF,
-		set_fn: SF,
-	) where
-		V: Migrate + Default + Send + Sync,
-		T: FromStr + ToString + Send + Sync + 'static,
-		GF: Fn(&PersisterShared<V>) -> T + Send + Sync + 'static,
-		SF: Fn(&PersisterShared<V>, T) -> Result<(), Error> + Send + Sync + 'static,
-	{
-		let p1 = p.clone();
-		let get_fn = move || get_fn(&p1);
-
-		let p2 = p.clone();
-		let set_fn = move |v| set_fn(&p2, v);
-
-		self.vars.insert(name, Box::new(BgVar { get_fn, set_fn }));
-	}
-
-	pub fn register_ro<V, T, GF>(&mut self, p: &PersisterShared<V>, name: &'static str, get_fn: GF)
-	where
-		V: Migrate + Default + Send + Sync,
-		T: FromStr + ToString + Send + Sync + 'static,
-		GF: Fn(&PersisterShared<V>) -> T + Send + Sync + 'static,
-	{
-		let p1 = p.clone();
-		let get_fn = move || get_fn(&p1);
-
-		let set_fn = move |_| Err(Error::Message(format!("Cannot set value of {}", name)));
-
-		self.vars.insert(name, Box::new(BgVar { get_fn, set_fn }));
-	}
-
-	pub fn get(&self, var: &str) -> Result<String, Error> {
-		Ok(self
-			.vars
-			.get(var)
-			.ok_or_message("variable does not exist")?
-			.get())
-	}
-
-	pub fn get_all(&self) -> Vec<(&'static str, String)> {
-		self.vars.iter().map(|(k, v)| (*k, v.get())).collect()
-	}
-
-	pub fn set(&self, var: &str, val: &str) -> Result<(), Error> {
-		self.vars
-			.get(var)
-			.ok_or_message("variable does not exist")?
-			.set(val)
-	}
-}
-
-impl Default for BgVars {
-	fn default() -> Self {
-		Self::new()
-	}
-}
-
-// ----
-
-trait BgVarTrait: Send + Sync + 'static {
-	fn get(&self) -> String;
-	fn set(&self, v: &str) -> Result<(), Error>;
-}
-
-struct BgVar<T, GF, SF>
-where
-	T: FromStr + ToString + Send + Sync + 'static,
-	GF: Fn() -> T + Send + Sync + 'static,
-	SF: Fn(T) -> Result<(), Error> + Sync + Send + 'static,
-{
-	get_fn: GF,
-	set_fn: SF,
-}
-
-impl<T, GF, SF> BgVarTrait for BgVar<T, GF, SF>
-where
-	T: FromStr + ToString + Sync + Send + 'static,
-	GF: Fn() -> T + Sync + Send + 'static,
-	SF: Fn(T) -> Result<(), Error> + Sync + Send + 'static,
-{
-	fn get(&self) -> String {
-		(self.get_fn)().to_string()
-	}
-
-	fn set(&self, vstr: &str) -> Result<(), Error> {
-		let value = vstr
-			.parse()
-			.map_err(|_| Error::Message(format!("invalid value: {}", vstr)))?;
-		(self.set_fn)(value)
-	}
-}
--- a/src/util/background/worker.rs
+++ b/src/util/background/worker.rs
@ -1,6 +1,6 @@
 use std::collections::HashMap;
 use std::sync::Arc;
-use std::time::Duration;
+use std::time::{Duration, Instant};

 use async_trait::async_trait;
 use futures::future::*;
@ -10,14 +10,10 @@ use serde::{Deserialize, Serialize};
 use tokio::select;
 use tokio::sync::{mpsc, watch};

-use crate::background::{WorkerInfo, WorkerStatus};
+use crate::background::WorkerInfo;
 use crate::error::Error;
 use crate::time::now_msec;

-// All workers that haven't exited for this time after an exit signal was recieved
-// will be interrupted in the middle of whatever they are doing.
-const EXIT_DEADLINE: Duration = Duration::from_secs(8);
-
 #[derive(PartialEq, Copy, Clone, Serialize, Deserialize, Debug)]
 pub enum WorkerState {
 	Busy,
@ -30,7 +26,7 @@ impl std::fmt::Display for WorkerState {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 		match self {
 			WorkerState::Busy => write!(f, "Busy"),
-			WorkerState::Throttled(_) => write!(f, "Busy*"),
+			WorkerState::Throttled(t) => write!(f, "Thr:{:.3}", t),
 			WorkerState::Idle => write!(f, "Idle"),
 			WorkerState::Done => write!(f, "Done"),
 		}
@ -41,8 +37,8 @@ impl std::fmt::Display for WorkerState {
 pub trait Worker: Send {
 	fn name(&self) -> String;

-	fn status(&self) -> WorkerStatus {
-		Default::default()
+	fn info(&self) -> Option<String> {
+		None
 	}

 	/// Work: do a basic unit of work, if one is available (otherwise, should return
@ -54,8 +50,10 @@ pub trait Worker: Send {
 	async fn work(&mut self, must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error>;

 	/// Wait for work: await for some task to become available.  This future can be interrupted in
-	/// the middle for any reason, for example if an interrupt signal was recieved.
-	async fn wait_for_work(&mut self) -> WorkerState;
+	/// the middle for any reason.  This future doesn't have to await on must_exit.changed(), we
+	/// are doing it for you.  Therefore it only receives a read refernce to must_exit which allows
+	/// it to check if we are exiting.
+	async fn wait_for_work(&mut self, must_exit: &watch::Receiver<bool>) -> WorkerState;
 }

 pub(crate) struct WorkerProcessor {
@ -95,9 +93,11 @@ impl WorkerProcessor {
 						let task_id = next_task_id;
 						next_task_id += 1;
 						let stop_signal = self.stop_signal.clone();
+						let stop_signal_worker = self.stop_signal.clone();
 						let mut worker = WorkerHandler {
 								task_id,
 								stop_signal,
+								stop_signal_worker,
 								worker: new_worker,
 								state: WorkerState::Busy,
 								errors: 0,
@ -119,7 +119,7 @@ impl WorkerProcessor {
 						match wi.get_mut(&worker.task_id) {
 							Some(i) => {
 								i.state = worker.state;
-								i.status = worker.worker.status();
+								i.info = worker.worker.info();
 								i.errors = worker.errors;
 								i.consecutive_errors = worker.consecutive_errors;
 								if worker.last_error.is_some() {
@ -130,7 +130,7 @@ impl WorkerProcessor {
 								wi.insert(worker.task_id, WorkerInfo {
 									name: worker.worker.name(),
 									state: worker.state,
-									status: worker.worker.status(),
+									info: worker.worker.info(),
 									errors: worker.errors,
 									consecutive_errors: worker.consecutive_errors,
 									last_error: worker.last_error.take(),
@ -153,14 +153,26 @@ impl WorkerProcessor {
 		}

 		// We are exiting, drain everything
+		let drain_half_time = Instant::now() + Duration::from_secs(5);
 		let drain_everything = async move {
-			while let Some(worker) = workers.next().await {
+			while let Some(mut worker) = workers.next().await {
+				if worker.state == WorkerState::Done {
 					info!(
-					"Worker {} (TID {}) exited (last state: {:?})",
+						"Worker {} (TID {}) exited",
 						worker.worker.name(),
-					worker.task_id,
-					worker.state
+						worker.task_id
 					);
+				} else if Instant::now() > drain_half_time {
+					warn!("Worker {} (TID {}) interrupted between two iterations in state {:?} (this should be fine)", worker.worker.name(), worker.task_id, worker.state);
+				} else {
+					workers.push(
+						async move {
+							worker.step().await;
+							worker
+						}
+						.boxed(),
+					);
+				}
 			}
 		};

@ -168,7 +180,7 @@ impl WorkerProcessor {
 			_ = drain_everything => {
 				info!("All workers exited peacefully \\o/");
 			}
-			_ = tokio::time::sleep(EXIT_DEADLINE) => {
+			_ = tokio::time::sleep(Duration::from_secs(9)) => {
 				error!("Some workers could not exit in time, we are cancelling some things in the middle");
 			}
 		}
@ -178,6 +190,7 @@ impl WorkerProcessor {
 struct WorkerHandler {
 	task_id: usize,
 	stop_signal: watch::Receiver<bool>,
+	stop_signal_worker: watch::Receiver<bool>,
 	worker: Box<dyn Worker>,
 	state: WorkerState,
 	errors: usize,
@ -212,19 +225,33 @@ impl WorkerHandler {
 			},
 			WorkerState::Throttled(delay) => {
 				// Sleep for given delay and go back to busy state
+				if !*self.stop_signal.borrow() {
 					select! {
-					_ = tokio::time::sleep(Duration::from_secs_f32(delay)) => {
+						_ = tokio::time::sleep(Duration::from_secs_f32(delay)) => (),
+						_ = self.stop_signal.changed() => (),
+					}
+				}
 				self.state = WorkerState::Busy;
 			}
-					_ = self.stop_signal.changed() => (),
-				}
-			}
 			WorkerState::Idle => {
+				if *self.stop_signal.borrow() {
 					select! {
-					new_st = self.worker.wait_for_work() => {
+						new_st = self.worker.wait_for_work(&self.stop_signal_worker) => {
 							self.state = new_st;
 						}
-					_ = self.stop_signal.changed() => (),
+						_ = tokio::time::sleep(Duration::from_secs(1)) => {
+							// stay in Idle state
+						}
+					}
+				} else {
+					select! {
+						new_st = self.worker.wait_for_work(&self.stop_signal_worker) => {
+							self.state = new_st;
+						}
+						_ = self.stop_signal.changed() => {
+							// stay in Idle state
+						}
+					}
 				}
 			}
 			WorkerState::Done => unreachable!(),
--- a/src/util/config.rs
+++ b/src/util/config.rs
@ -34,11 +34,7 @@ pub struct Config {
 	pub compression_level: Option<i32>,

 	/// RPC secret key: 32 bytes hex encoded
-	/// Note: When using `read_config` this should never be `None`
-	pub rpc_secret: Option<String>,
-
-	/// Optional file where RPC secret key is read from
-	pub rpc_secret_file: Option<String>,
+	pub rpc_secret: String,

 	/// Address to bind for RPC
 	pub rpc_bind_addr: SocketAddr,
@ -181,31 +177,7 @@ pub fn read_config(config_file: PathBuf) -> Result<Config, Error> {
 	let mut config = String::new();
 	file.read_to_string(&mut config)?;

-	let mut parsed_config: Config = toml::from_str(&config)?;
-
-	match (&parsed_config.rpc_secret, &parsed_config.rpc_secret_file) {
-		(Some(_), None) => {
-			// no-op
-		}
-		(Some(_), Some(_)) => {
-			return Err("only one of `rpc_secret` and `rpc_secret_file` can be set".into())
-		}
-		(None, Some(rpc_secret_file_path_string)) => {
-			let mut rpc_secret_file = std::fs::OpenOptions::new()
-				.read(true)
-				.open(rpc_secret_file_path_string)?;
-			let mut rpc_secret_from_file = String::new();
-			rpc_secret_file.read_to_string(&mut rpc_secret_from_file)?;
-			// trim_end: allows for use case such as `echo "$(openssl rand -hex 32)" > somefile`.
-			//           also editors sometimes add a trailing newline
-			parsed_config.rpc_secret = Some(String::from(rpc_secret_from_file.trim_end()));
-		}
-		(None, None) => {
-			return Err("either `rpc_secret` or `rpc_secret_file` needs to be set".into())
-		}
-	};
-
-	Ok(parsed_config)
+	Ok(toml::from_str(&config)?)
 }

 fn default_compression() -> Option<i32> {
@ -261,123 +233,3 @@ where

 	deserializer.deserialize_any(OptionVisitor)
 }
-
-#[cfg(test)]
-mod tests {
-	use crate::error::Error;
-	use std::fs::File;
-	use std::io::Write;
-
-	#[test]
-	fn test_rpc_secret_is_required() -> Result<(), Error> {
-		let path1 = mktemp::Temp::new_file()?;
-		let mut file1 = File::create(path1.as_path())?;
-		writeln!(
-			file1,
-			r#"
-			metadata_dir = "/tmp/garage/meta"
-			data_dir = "/tmp/garage/data"
-			replication_mode = "3"
-			rpc_bind_addr = "[::]:3901"
-		
-			[s3_api]
-			s3_region = "garage"
-			api_bind_addr = "[::]:3900"
-			"#
-		)?;
-		assert_eq!(
-			"either `rpc_secret` or `rpc_secret_file` needs to be set",
-			super::read_config(path1.to_path_buf())
-				.unwrap_err()
-				.to_string()
-		);
-		drop(path1);
-		drop(file1);
-
-		let path2 = mktemp::Temp::new_file()?;
-		let mut file2 = File::create(path2.as_path())?;
-		writeln!(
-			file2,
-			r#"
-			metadata_dir = "/tmp/garage/meta"
-			data_dir = "/tmp/garage/data"
-			replication_mode = "3"
-			rpc_bind_addr = "[::]:3901"
-			rpc_secret = "foo"
-
-			[s3_api]
-			s3_region = "garage"
-			api_bind_addr = "[::]:3900"
-			"#
-		)?;
-
-		let config = super::read_config(path2.to_path_buf())?;
-		assert_eq!("foo", config.rpc_secret.unwrap());
-		drop(path2);
-		drop(file2);
-
-		Ok(())
-	}
-
-	#[test]
-	fn test_rpc_secret_file_works() -> Result<(), Error> {
-		let path_secret = mktemp::Temp::new_file()?;
-		let mut file_secret = File::create(path_secret.as_path())?;
-		writeln!(file_secret, "foo")?;
-		drop(file_secret);
-
-		let path_config = mktemp::Temp::new_file()?;
-		let mut file_config = File::create(path_config.as_path())?;
-		let path_secret_path = path_secret.as_path().display();
-		writeln!(
-			file_config,
-			r#"
-			metadata_dir = "/tmp/garage/meta"
-			data_dir = "/tmp/garage/data"
-			replication_mode = "3"
-			rpc_bind_addr = "[::]:3901"
-			rpc_secret_file = "{path_secret_path}"
-		
-			[s3_api]
-			s3_region = "garage"
-			api_bind_addr = "[::]:3900"
-			"#
-		)?;
-		let config = super::read_config(path_config.to_path_buf())?;
-		assert_eq!("foo", config.rpc_secret.unwrap());
-		drop(path_config);
-		drop(path_secret);
-		drop(file_config);
-		Ok(())
-	}
-
-	#[test]
-	fn test_rcp_secret_and_rpc_secret_file_cannot_be_set_both() -> Result<(), Error> {
-		let path_config = mktemp::Temp::new_file()?;
-		let mut file_config = File::create(path_config.as_path())?;
-		writeln!(
-			file_config,
-			r#"
-			metadata_dir = "/tmp/garage/meta"
-			data_dir = "/tmp/garage/data"
-			replication_mode = "3"
-			rpc_bind_addr = "[::]:3901"
-			rpc_secret= "dummy"
-			rpc_secret_file = "dummy"
-		
-			[s3_api]
-			s3_region = "garage"
-			api_bind_addr = "[::]:3900"
-			"#
-		)?;
-		assert_eq!(
-			"only one of `rpc_secret` and `rpc_secret_file` can be set",
-			super::read_config(path_config.to_path_buf())
-				.unwrap_err()
-				.to_string()
-		);
-		drop(path_config);
-		drop(file_config);
-		Ok(())
-	}
-}
--- a/src/util/data.rs
+++ b/src/util/data.rs
@ -140,3 +140,34 @@ pub fn fasthash(data: &[u8]) -> FastHash {
 pub fn gen_uuid() -> Uuid {
 	rand::thread_rng().gen::<[u8; 32]>().into()
 }
+
+// RMP serialization with names of fields and variants
+
+/// Serialize to MessagePack
+pub fn rmp_to_vec_all_named<T>(val: &T) -> Result<Vec<u8>, rmp_serde::encode::Error>
+where
+	T: Serialize + ?Sized,
+{
+	let mut wr = Vec::with_capacity(128);
+	let mut se = rmp_serde::Serializer::new(&mut wr)
+		.with_struct_map()
+		.with_string_variants();
+	val.serialize(&mut se)?;
+	Ok(wr)
+}
+
+/// Serialize to JSON, truncating long result
+pub fn debug_serialize<T: Serialize>(x: T) -> String {
+	match serde_json::to_string(&x) {
+		Ok(ss) => {
+			if ss.len() > 100 {
+				// TODO this can panic if 100 is not a codepoint boundary, but inside a 2 Bytes
+				// (or more) codepoint
+				ss[..100].to_string()
+			} else {
+				ss
+			}
+		}
+		Err(e) => format!("<JSON serialization error: {}>", e),
+	}
+}
--- a/src/util/encode.rs
+++ b/src/util/encode.rs
@ -1,42 +0,0 @@
-use serde::{Deserialize, Serialize};
-
-/// Serialize to MessagePacki, without versionning
-/// (see garage_util::migrate for functions that manage versionned
-/// data formats)
-pub fn nonversioned_encode<T>(val: &T) -> Result<Vec<u8>, rmp_serde::encode::Error>
-where
-	T: Serialize + ?Sized,
-{
-	let mut wr = Vec::with_capacity(128);
-	let mut se = rmp_serde::Serializer::new(&mut wr)
-		.with_struct_map()
-		.with_string_variants();
-	val.serialize(&mut se)?;
-	Ok(wr)
-}
-
-/// Deserialize from MessagePacki, without versionning
-/// (see garage_util::migrate for functions that manage versionned
-/// data formats)
-pub fn nonversioned_decode<T>(bytes: &[u8]) -> Result<T, rmp_serde::decode::Error>
-where
-	T: for<'de> Deserialize<'de> + ?Sized,
-{
-	rmp_serde::decode::from_read_ref::<_, T>(bytes)
-}
-
-/// Serialize to JSON, truncating long result
-pub fn debug_serialize<T: Serialize>(x: T) -> String {
-	match serde_json::to_string(&x) {
-		Ok(ss) => {
-			if ss.len() > 100 {
-				// TODO this can panic if 100 is not a codepoint boundary, but inside a 2 Bytes
-				// (or more) codepoint
-				ss[..100].to_string()
-			} else {
-				ss
-			}
-		}
-		Err(e) => format!("<JSON serialization error: {}>", e),
-	}
-}
--- a/src/util/error.rs
+++ b/src/util/error.rs
@ -7,7 +7,6 @@ use err_derive::Error;
 use serde::{de::Visitor, Deserialize, Deserializer, Serialize, Serializer};

 use crate::data::*;
-use crate::encode::debug_serialize;

 /// Regroup all Garage errors
 #[derive(Debug, Error)]
--- a/src/util/formater.rs
+++ b/src/util/formater.rs
@ -1,4 +1,4 @@
-pub fn format_table_to_string(data: Vec<String>) -> String {
+pub fn format_table(data: Vec<String>) {
 	let data = data
 		.iter()
 		.map(|s| s.split('\t').collect::<Vec<_>>())
@ -24,9 +24,5 @@ pub fn format_table_to_string(data: Vec<String>) -> String {
 		out.push('\n');
 	}

-	out
-}
-
-pub fn format_table(data: Vec<String>) {
-	print!("{}", format_table_to_string(data));
+	print!("{}", out);
 }
--- a/src/util/lib.rs
+++ b/src/util/lib.rs
@ -8,12 +8,11 @@ pub mod background;
 pub mod config;
 pub mod crdt;
 pub mod data;
-pub mod encode;
 pub mod error;
 pub mod formater;
 pub mod metrics;
-pub mod migrate;
 pub mod persister;
 pub mod time;
+pub mod token_bucket;
 pub mod tranquilizer;
 pub mod version;
--- a/src/util/migrate.rs
+++ b/src/util/migrate.rs
@ -1,159 +0,0 @@
-use serde::{Deserialize, Serialize};
-
-/// Indicates that this type has an encoding that can be migrated from
-/// a previous version upon upgrades of Garage.
-pub trait Migrate: Serialize + for<'de> Deserialize<'de> + 'static {
-	/// A sequence of bytes to add at the beginning of the serialized
-	/// string, to identify that the data is of this version.
-	const VERSION_MARKER: &'static [u8] = b"";
-
-	/// The previous version of this data type, from which items of this version
-	/// can be migrated.
-	type Previous: Migrate;
-
-	/// The migration function that transforms a value decoded in the old format
-	/// to an up-to-date value.
-	fn migrate(previous: Self::Previous) -> Self;
-
-	/// Decode an encoded version of this type, going through a migration if necessary.
-	fn decode(bytes: &[u8]) -> Option<Self> {
-		let marker_len = Self::VERSION_MARKER.len();
-		if bytes.get(..marker_len) == Some(Self::VERSION_MARKER) {
-			if let Ok(value) = rmp_serde::decode::from_read_ref::<_, Self>(&bytes[marker_len..]) {
-				return Some(value);
-			}
-		}
-
-		Self::Previous::decode(bytes).map(Self::migrate)
-	}
-
-	/// Encode this type with optionnal version marker
-	fn encode(&self) -> Result<Vec<u8>, rmp_serde::encode::Error> {
-		let mut wr = Vec::with_capacity(128);
-		wr.extend_from_slice(Self::VERSION_MARKER);
-		let mut se = rmp_serde::Serializer::new(&mut wr)
-			.with_struct_map()
-			.with_string_variants();
-		self.serialize(&mut se)?;
-		Ok(wr)
-	}
-}
-
-/// Indicates that this type has no previous encoding version to be migrated from.
-pub trait InitialFormat: Serialize + for<'de> Deserialize<'de> + 'static {
-	/// A sequence of bytes to add at the beginning of the serialized
-	/// string, to identify that the data is of this version.
-	const VERSION_MARKER: &'static [u8] = b"";
-}
-
-impl<T: InitialFormat> Migrate for T {
-	const VERSION_MARKER: &'static [u8] = <T as InitialFormat>::VERSION_MARKER;
-
-	type Previous = NoPrevious;
-
-	fn migrate(_previous: Self::Previous) -> Self {
-		unreachable!();
-	}
-}
-
-/// Internal type used by InitialFormat, not meant for general use.
-#[derive(Serialize, Deserialize)]
-pub enum NoPrevious {}
-
-impl Migrate for NoPrevious {
-	type Previous = NoPrevious;
-
-	fn migrate(_previous: Self::Previous) -> Self {
-		unreachable!();
-	}
-
-	fn decode(_bytes: &[u8]) -> Option<Self> {
-		None
-	}
-
-	fn encode(&self) -> Result<Vec<u8>, rmp_serde::encode::Error> {
-		unreachable!()
-	}
-}
-
-#[cfg(test)]
-mod test {
-	use super::*;
-
-	#[derive(Serialize, Deserialize, PartialEq, Eq, Debug)]
-	struct V1 {
-		a: usize,
-		b: String,
-	}
-	impl InitialFormat for V1 {}
-
-	#[derive(Serialize, Deserialize, PartialEq, Eq, Debug)]
-	struct V2 {
-		a: usize,
-		b: Vec<String>,
-		c: String,
-	}
-	impl Migrate for V2 {
-		const VERSION_MARKER: &'static [u8] = b"GtestV2";
-		type Previous = V1;
-		fn migrate(prev: V1) -> V2 {
-			V2 {
-				a: prev.a,
-				b: vec![prev.b],
-				c: String::new(),
-			}
-		}
-	}
-
-	#[test]
-	fn test_v1() {
-		let x = V1 {
-			a: 12,
-			b: "hello".into(),
-		};
-		let x_enc = x.encode().unwrap();
-		let y = V1::decode(&x_enc).unwrap();
-		assert_eq!(x, y);
-	}
-
-	#[test]
-	fn test_v2() {
-		let x = V2 {
-			a: 12,
-			b: vec!["hello".into(), "world".into()],
-			c: "plop".into(),
-		};
-		let x_enc = x.encode().unwrap();
-		assert_eq!(&x_enc[..V2::VERSION_MARKER.len()], V2::VERSION_MARKER);
-		let y = V2::decode(&x_enc).unwrap();
-		assert_eq!(x, y);
-	}
-
-	#[test]
-	fn test_migrate() {
-		let x = V1 {
-			a: 12,
-			b: "hello".into(),
-		};
-		let x_enc = x.encode().unwrap();
-
-		let xx = V1::decode(&x_enc).unwrap();
-		assert_eq!(x, xx);
-
-		let y = V2::decode(&x_enc).unwrap();
-		assert_eq!(
-			y,
-			V2 {
-				a: 12,
-				b: vec!["hello".into()],
-				c: "".into(),
-			}
-		);
-
-		let y_enc = y.encode().unwrap();
-		assert_eq!(&y_enc[..V2::VERSION_MARKER.len()], V2::VERSION_MARKER);
-
-		let z = V2::decode(&y_enc).unwrap();
-		assert_eq!(y, z);
-	}
-}
--- a/src/util/persister.rs
+++ b/src/util/persister.rs
@ -1,19 +1,23 @@
 use std::io::{Read, Write};
 use std::path::{Path, PathBuf};
-use std::sync::{Arc, RwLock};

 use tokio::io::{AsyncReadExt, AsyncWriteExt};

-use crate::error::Error;
-use crate::migrate::Migrate;
+use serde::{Deserialize, Serialize};

-pub struct Persister<T: Migrate> {
+use crate::data::*;
+use crate::error::Error;
+
+pub struct Persister<T: Serialize + for<'de> Deserialize<'de>> {
 	path: PathBuf,

 	_marker: std::marker::PhantomData<T>,
 }

-impl<T: Migrate> Persister<T> {
+impl<T> Persister<T>
+where
+	T: Serialize + for<'de> Deserialize<'de>,
+{
 	pub fn new(base_dir: &Path, file_name: &str) -> Self {
 		let mut path = base_dir.to_path_buf();
 		path.push(file_name);
@ -23,37 +27,18 @@ impl<T: Migrate> Persister<T> {
 		}
 	}

-	fn decode(&self, bytes: &[u8]) -> Result<T, Error> {
-		match T::decode(bytes) {
-			Some(v) => Ok(v),
-			None => {
-				error!(
-					"Unable to decode persisted data file {}",
-					self.path.display()
-				);
-				for line in hexdump::hexdump_iter(bytes) {
-					debug!("{}", line);
-				}
-				Err(Error::Message(format!(
-					"Unable to decode persisted data file {}",
-					self.path.display()
-				)))
-			}
-		}
-	}
-
 	pub fn load(&self) -> Result<T, Error> {
 		let mut file = std::fs::OpenOptions::new().read(true).open(&self.path)?;

 		let mut bytes = vec![];
 		file.read_to_end(&mut bytes)?;

-		let value = self.decode(&bytes[..])?;
+		let value = rmp_serde::decode::from_read_ref(&bytes[..])?;
 		Ok(value)
 	}

 	pub fn save(&self, t: &T) -> Result<(), Error> {
-		let bytes = t.encode()?;
+		let bytes = rmp_to_vec_all_named(t)?;

 		let mut file = std::fs::OpenOptions::new()
 			.write(true)
@ -72,12 +57,12 @@ impl<T: Migrate> Persister<T> {
 		let mut bytes = vec![];
 		file.read_to_end(&mut bytes).await?;

-		let value = self.decode(&bytes[..])?;
+		let value = rmp_serde::decode::from_read_ref(&bytes[..])?;
 		Ok(value)
 	}

 	pub async fn save_async(&self, t: &T) -> Result<(), Error> {
-		let bytes = t.encode()?;
+		let bytes = rmp_to_vec_all_named(t)?;

 		let mut file = tokio::fs::File::create(&self.path).await?;
 		file.write_all(&bytes[..]).await?;
@ -85,36 +70,3 @@ impl<T: Migrate> Persister<T> {
 		Ok(())
 	}
 }
-
-pub struct PersisterShared<V: Migrate + Default>(Arc<(Persister<V>, RwLock<V>)>);
-
-impl<V: Migrate + Default> Clone for PersisterShared<V> {
-	fn clone(&self) -> PersisterShared<V> {
-		PersisterShared(self.0.clone())
-	}
-}
-
-impl<V: Migrate + Default> PersisterShared<V> {
-	pub fn new(base_dir: &Path, file_name: &str) -> Self {
-		let persister = Persister::new(base_dir, file_name);
-		let value = persister.load().unwrap_or_default();
-		Self(Arc::new((persister, RwLock::new(value))))
-	}
-
-	pub fn get_with<F, R>(&self, f: F) -> R
-	where
-		F: FnOnce(&V) -> R,
-	{
-		let value = self.0 .1.read().unwrap();
-		f(&value)
-	}
-
-	pub fn set_with<F>(&self, f: F) -> Result<(), Error>
-	where
-		F: FnOnce(&mut V),
-	{
-		let mut value = self.0 .1.write().unwrap();
-		f(&mut value);
-		self.0 .0.save(&value)
-	}
-}
--- a/src/util/token_bucket.rs
+++ b/src/util/token_bucket.rs
@ -0,0 +1,40 @@
+use std::time::{Duration, Instant};
+
+use tokio::time::sleep;
+
+pub struct TokenBucket {
+	// Replenish rate: number of tokens per second
+	replenish_rate: u64,
+	// Current number of tokens
+	tokens: u64,
+	// Last replenish time
+	last_replenish: Instant,
+}
+
+impl TokenBucket {
+	pub fn new(replenish_rate: u64) -> Self {
+		Self {
+			replenish_rate,
+			tokens: 0,
+			last_replenish: Instant::now(),
+		}
+	}
+
+	pub async fn take(&mut self, tokens: u64) {
+		while self.tokens < tokens {
+			let needed = tokens - self.tokens;
+			let delay = (needed as f64) / (self.replenish_rate as f64);
+			sleep(Duration::from_secs_f64(delay)).await;
+			self.replenish();
+		}
+		self.tokens -= tokens;
+	}
+
+	pub fn replenish(&mut self) {
+		let now = Instant::now();
+		let new_tokens =
+			((now - self.last_replenish).as_secs_f64() * (self.replenish_rate as f64)) as u64;
+		self.tokens += new_tokens;
+		self.last_replenish = now;
+	}
+}
--- a/src/web/Cargo.toml
+++ b/src/web/Cargo.toml
@ -1,6 +1,6 @@
 [package]
 name = "garage_web"
-version = "0.8.1"
+version = "0.8.0"
 authors = ["Alex Auvolat <alex@adnab.me>", "Quentin Dufour <quentin@dufour.io>"]
 edition = "2018"
 license = "AGPL-3.0"
@ -14,10 +14,10 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

 [dependencies]
-garage_api = { version = "0.8.1", path = "../api" }
-garage_model = { version = "0.8.1", path = "../model" }
-garage_util = { version = "0.8.1", path = "../util" }
-garage_table = { version = "0.8.1", path = "../table" }
+garage_api = { version = "0.8.0", path = "../api" }
+garage_model = { version = "0.8.0", path = "../model" }
+garage_util = { version = "0.8.0", path = "../util" }
+garage_table = { version = "0.8.0", path = "../table" }

 err-derive = "0.3"
 tracing = "0.1.30"