src/block/manager.rs

@@ -90,6 +90,15 @@ pub struct BlockManager {
 	tx_scrub_command: 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,
+}
+
 // This custom struct contains functions that must only be ran
 // when the lock is held. We ensure that it is the case by storing
 // it INSIDE a Mutex.
@@ -314,6 +323,31 @@ impl BlockManager {
 		let _ = self.tx_scrub_command.send(cmd).await;
 	}
 
+	/// 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)
+	}
+
 	//// ----- Managing the reference counter ----
 
 	/// Increment the number of time a block is used, putting it to resynchronization if it is

src/block/rc.rs

@@ -169,4 +169,11 @@ 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,
+		}
+	}
 }

src/block/resync.rs

@@ -540,9 +540,9 @@ impl Worker for ResyncWorker {
 /// and the time of the last try.
 /// Used to implement exponential backoff.
 #[derive(Clone, Copy, Debug)]
-struct ErrorCounter {
-	errors: u64,
-	last_try: u64,
+pub(crate) struct ErrorCounter {
+	pub(crate) errors: u64,
+	pub(crate) last_try: u64,
 }
 
 impl ErrorCounter {
@@ -553,12 +553,13 @@ impl ErrorCounter {
 		}
 	}
 
-	fn decode(data: &[u8]) -> Self {
+	pub(crate) 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),
@@ -578,7 +579,8 @@ impl ErrorCounter {
 		(RESYNC_RETRY_DELAY.as_millis() as u64)
 			<< std::cmp::min(self.errors - 1, RESYNC_RETRY_DELAY_MAX_BACKOFF_POWER)
 	}
-	fn next_try(&self) -> u64 {
+
+	pub(crate) fn next_try(&self) -> u64 {
 		self.last_try + self.delay_msec()
 	}
 }

src/garage/admin.rs

@@ -15,6 +15,7 @@ use garage_table::*;
 
 use garage_rpc::*;
 
+use garage_block::manager::BlockResyncErrorInfo;
 use garage_block::repair::ScrubWorkerCommand;
 
 use garage_model::bucket_alias_table::*;
@@ -24,6 +25,7 @@ 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::version_table::Version;
 
 use crate::cli::*;
 use crate::repair::online::launch_online_repair;
@@ -38,7 +40,8 @@ pub enum AdminRpc {
 	LaunchRepair(RepairOpt),
 	Migrate(MigrateOpt),
 	Stats(StatsOpt),
-	Worker(WorkerOpt),
+	Worker(WorkerOperation),
+	BlockOperation(BlockOperation),
 
 	// Replies
 	Ok(String),
@@ -55,6 +58,12 @@ pub enum AdminRpc {
 		WorkerListOpt,
 	),
 	WorkerInfo(usize, garage_util::background::WorkerInfo),
+	BlockErrorList(Vec<BlockResyncErrorInfo>),
+	BlockInfo {
+		hash: Hash,
+		refcount: u64,
+		versions: Vec<Result<Version, Uuid>>,
+	},
 }
 
 impl Rpc for AdminRpc {
@@ -74,6 +83,8 @@ impl AdminRpcHandler {
 		admin
 	}
 
+	// ================ BUCKET COMMANDS ====================
+
 	async fn handle_bucket_cmd(&self, cmd: &BucketOperation) -> Result<AdminRpc, Error> {
 		match cmd {
 			BucketOperation::List => self.handle_list_buckets().await,
@@ -552,6 +563,8 @@ 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,
@@ -689,6 +702,8 @@ 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(
@@ -705,6 +720,8 @@ 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(
@@ -748,6 +765,8 @@ impl AdminRpcHandler {
 		}
 	}
 
+	// ================ STATS COMMANDS ====================
+
 	async fn handle_stats(&self, opt: StatsOpt) -> Result<AdminRpc, Error> {
 		if opt.all_nodes {
 			let mut ret = String::new();
@@ -873,27 +892,27 @@ impl AdminRpcHandler {
 		Ok(())
 	}
 
-	// ----
+	// ================ WORKER COMMANDS ====================
 
-	async fn handle_worker_cmd(&self, opt: WorkerOpt) -> Result<AdminRpc, Error> {
-		match opt.cmd {
-			WorkerCmd::List { opt } => {
+	async fn handle_worker_cmd(&self, cmd: &WorkerOperation) -> Result<AdminRpc, Error> {
+		match cmd {
+			WorkerOperation::List { opt } => {
 				let workers = self.garage.background.get_worker_info();
-				Ok(AdminRpc::WorkerList(workers, opt))
+				Ok(AdminRpc::WorkerList(workers, *opt))
 			}
-			WorkerCmd::Info { tid } => {
+			WorkerOperation::Info { tid } => {
 				let info = self
 					.garage
 					.background
 					.get_worker_info()
-					.get(&tid)
+					.get(tid)
 					.ok_or_bad_request(format!("No worker with TID {}", tid))?
 					.clone();
-				Ok(AdminRpc::WorkerInfo(tid, info))
+				Ok(AdminRpc::WorkerInfo(*tid, info))
 			}
-			WorkerCmd::Set { opt } => match opt {
+			WorkerOperation::Set { opt } => match opt {
 				WorkerSetCmd::ScrubTranquility { tranquility } => {
-					let scrub_command = ScrubWorkerCommand::SetTranquility(tranquility);
+					let scrub_command = ScrubWorkerCommand::SetTranquility(*tranquility);
 					self.garage
 						.block_manager
 						.send_scrub_command(scrub_command)
@@ -904,7 +923,7 @@ impl AdminRpcHandler {
 					self.garage
 						.block_manager
 						.resync
-						.set_n_workers(worker_count)
+						.set_n_workers(*worker_count)
 						.await?;
 					Ok(AdminRpc::Ok("Number of resync workers updated".into()))
 				}
@@ -912,13 +931,57 @@ impl AdminRpcHandler {
 					self.garage
 						.block_manager
 						.resync
-						.set_tranquility(tranquility)
+						.set_tranquility(*tranquility)
 						.await?;
 					Ok(AdminRpc::Ok("Resync tranquility updated".into()))
 				}
 			},
 		}
 	}
+
+	// ================ 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())
+					.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::BlockInfo {
+					hash,
+					refcount,
+					versions,
+				})
+			}
+			BlockOperation::RetryNow { .. } => {
+				Err(GarageError::Message("not implemented".into()).into())
+			}
+			BlockOperation::Purge { .. } => {
+				Err(GarageError::Message("not implemented".into()).into())
+			}
+		}
+	}
 }
 
 #[async_trait]
@@ -934,7 +997,8 @@ 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(opt) => self.handle_worker_cmd(opt.clone()).await,
+			AdminRpc::Worker(wo) => self.handle_worker_cmd(wo).await,
+			AdminRpc::BlockOperation(bo) => self.handle_block_cmd(bo).await,
 			m => Err(GarageError::unexpected_rpc_message(m).into()),
 		}
 	}

src/garage/cli/cmd.rs

@@ -41,6 +41,9 @@ 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!(),
 	}
 }
@@ -191,6 +194,16 @@ pub async fn cmd_admin(
 		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);
+		}
 		r => {
 			error!("Unexpected response: {:?}", r);
 		}

src/garage/cli/structs.rs

@@ -49,7 +49,11 @@ pub enum Command {
 
 	/// Manage background workers
 	#[structopt(name = "worker", version = garage_version())]
-	Worker(WorkerOpt),
+	Worker(WorkerOperation),
+
+	/// Low-level debug operations on data blocks
+	#[structopt(name = "block", version = garage_version())]
+	Block(BlockOperation),
 }
 
 #[derive(StructOpt, Debug)]
@@ -502,14 +506,8 @@ 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 WorkerCmd {
+pub enum WorkerOperation {
 	/// List all workers on Garage node
 	#[structopt(name = "list", version = garage_version())]
 	List {
@@ -549,3 +547,34 @@ pub enum WorkerSetCmd {
 	#[structopt(name = "resync-tranquility", version = garage_version())]
 	ResyncTranquility { tranquility: u32 },
 }
+
+#[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
+		blocks: Vec<String>,
+	},
+}

src/garage/cli/util.rs

@@ -3,14 +3,17 @@ use std::time::Duration;
 
 use garage_util::background::*;
 use garage_util::crdt::*;
-use garage_util::data::Uuid;
+use garage_util::data::*;
 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;
 
@@ -353,3 +356,57 @@ pub fn print_worker_info(tid: usize, info: WorkerInfo) {
 	}
 	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\tPath\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");
+	}
+}

src/table/util.rs

@@ -49,3 +49,9 @@ impl EnumerationOrder {
 		}
 	}
 }
+
+impl Default for EnumerationOrder {
+	fn default() -> Self {
+		EnumerationOrder::Forward
+	}
+}