(not well tested) use merkle tree for sync

This commit is contained in:
Alex 2021-03-11 18:28:03 +01:00
parent 94f3d28774
commit 046b649bcc
11 changed files with 765 additions and 985 deletions

View file

@ -25,26 +25,11 @@ impl Repair {
if todo(RepairWhat::Tables) {
info!("Launching a full sync of tables");
self.garage
.bucket_table
.syncer
.add_full_scan();
self.garage
.object_table
.syncer
.add_full_scan();
self.garage
.version_table
.syncer
.add_full_scan();
self.garage
.block_ref_table
.syncer
.add_full_scan();
self.garage
.key_table
.syncer
.add_full_scan();
self.garage.bucket_table.syncer.add_full_sync();
self.garage.object_table.syncer.add_full_sync();
self.garage.version_table.syncer.add_full_sync();
self.garage.block_ref_table.syncer.add_full_sync();
self.garage.key_table.syncer.add_full_sync();
}
// TODO: wait for full sync to finish before proceeding to the rest?
@ -78,7 +63,9 @@ impl Repair {
async fn repair_versions(&self, must_exit: &watch::Receiver<bool>) -> Result<(), Error> {
let mut pos = vec![];
while let Some((item_key, item_bytes)) = self.garage.version_table.data.store.get_gt(&pos)? {
while let Some((item_key, item_bytes)) =
self.garage.version_table.data.store.get_gt(&pos)?
{
pos = item_key.to_vec();
let version = rmp_serde::decode::from_read_ref::<_, Version>(item_bytes.as_ref())?;
@ -126,7 +113,9 @@ impl Repair {
async fn repair_block_ref(&self, must_exit: &watch::Receiver<bool>) -> Result<(), Error> {
let mut pos = vec![];
while let Some((item_key, item_bytes)) = self.garage.block_ref_table.data.store.get_gt(&pos)? {
while let Some((item_key, item_bytes)) =
self.garage.block_ref_table.data.store.get_gt(&pos)?
{
pos = item_key.to_vec();
let block_ref = rmp_serde::decode::from_read_ref::<_, BlockRef>(item_bytes.as_ref())?;

View file

@ -7,8 +7,8 @@ use garage_rpc::membership::System;
use garage_rpc::rpc_client::RpcHttpClient;
use garage_rpc::rpc_server::RpcServer;
use garage_table::replication::sharded::*;
use garage_table::replication::fullcopy::*;
use garage_table::replication::sharded::*;
use garage_table::*;
use crate::block::*;

View file

@ -183,7 +183,7 @@ impl Ring {
let partition_top =
u16::from_be_bytes(partition.location.as_slice()[0..2].try_into().unwrap());
assert!(partition_top & PARTITION_MASK_U16 == top & PARTITION_MASK_U16);
assert_eq!(partition_top & PARTITION_MASK_U16, top & PARTITION_MASK_U16);
assert!(n <= partition.nodes.len());
partition.nodes[..n].iter().cloned().collect::<Vec<_>>()

View file

@ -1,16 +1,16 @@
use std::sync::Arc;
use log::warn;
use sled::Transactional;
use serde_bytes::ByteBuf;
use sled::Transactional;
use garage_util::background::BackgroundRunner;
use garage_util::data::*;
use garage_util::error::*;
use garage_util::background::BackgroundRunner;
use crate::schema::*;
use crate::merkle::*;
use crate::crdt::CRDT;
use crate::merkle::*;
use crate::schema::*;
pub struct TableData<F: TableSchema> {
pub name: String,
@ -20,7 +20,10 @@ pub struct TableData<F: TableSchema> {
pub(crate) merkle_updater: Arc<MerkleUpdater>,
}
impl<F> TableData<F> where F: TableSchema {
impl<F> TableData<F>
where
F: TableSchema,
{
pub fn new(
name: String,
instance: F,

View file

@ -7,11 +7,11 @@ pub mod crdt;
pub mod schema;
pub mod util;
pub mod data;
pub mod merkle;
pub mod replication;
pub mod data;
pub mod sync;
pub mod table;
pub mod table_sync;
pub use schema::*;
pub use table::*;

View file

@ -15,6 +15,19 @@ use garage_util::background::BackgroundRunner;
use garage_util::data::*;
use garage_util::error::Error;
pub type MerklePartition = [u8; 2];
pub fn hash_of_merkle_partition(p: MerklePartition) -> Hash {
let mut partition_pos = [0u8; 32];
partition_pos[0..2].copy_from_slice(&p[..]);
partition_pos.into()
}
pub fn hash_of_merkle_partition_opt(p: Option<MerklePartition>) -> Hash {
p.map(hash_of_merkle_partition)
.unwrap_or([0xFFu8; 32].into())
}
// This modules partitions the data in 2**16 partitions, based on the top
// 16 bits (two bytes) of item's partition keys' hashes.
// It builds one Merkle tree for each of these 2**16 partitions.
@ -37,10 +50,10 @@ pub(crate) struct MerkleUpdater {
empty_node_hash: Hash,
}
#[derive(Clone)]
#[derive(Clone, Serialize, Deserialize)]
pub struct MerkleNodeKey {
// partition: first 16 bits (two bytes) of the partition_key's hash
pub partition: [u8; 2],
pub partition: MerklePartition,
// prefix: a prefix for the hash of full keys, i.e. hash(hash(partition_key)+sort_key)
pub prefix: Vec<u8>,
@ -214,8 +227,11 @@ impl MerkleUpdater {
// insertion and replace current node by an intermediary node
let (pos1, h1) = {
let key2 = key.next_key(blake2sum(&exlf_key[..]));
let subhash =
self.put_node_txn(tx, &key2, &MerkleNode::Leaf(exlf_key, exlf_hash))?;
let subhash = self.put_node_txn(
tx,
&key2,
&MerkleNode::Leaf(exlf_key, exlf_hash),
)?;
(key2.prefix[i], subhash)
};
let (pos2, h2) = {
@ -280,14 +296,11 @@ impl MerkleUpdater {
}
// Access a node in the Merkle tree, used by the sync protocol
pub(crate) fn read_node(
&self,
k: &MerkleNodeKey,
) -> Result<MerkleNode, Error> {
pub(crate) fn read_node(&self, k: &MerkleNodeKey) -> Result<MerkleNode, Error> {
let ent = self.merkle_tree.get(k.encode())?;
match ent {
None => Ok(MerkleNode::Empty),
Some(v) => Ok(rmp_serde::decode::from_read_ref::<_, MerkleNode>(&v[..])?)
Some(v) => Ok(rmp_serde::decode::from_read_ref::<_, MerkleNode>(&v[..])?),
}
}
}
@ -341,29 +354,75 @@ fn test_intermediate_aux() {
let mut v = vec![];
intermediate_set_child(&mut v, 12u8, [12u8; 32].into());
assert!(v == vec![(12u8, [12u8; 32].into())]);
assert_eq!(v, vec![(12u8, [12u8; 32].into())]);
intermediate_set_child(&mut v, 42u8, [42u8; 32].into());
assert!(v == vec![(12u8, [12u8; 32].into()), (42u8, [42u8; 32].into())]);
assert_eq!(
v,
vec![(12u8, [12u8; 32].into()), (42u8, [42u8; 32].into())]
);
intermediate_set_child(&mut v, 4u8, [4u8; 32].into());
assert!(v == vec![(4u8, [4u8; 32].into()), (12u8, [12u8; 32].into()), (42u8, [42u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(12u8, [12u8; 32].into()),
(42u8, [42u8; 32].into())
]
);
intermediate_set_child(&mut v, 12u8, [8u8; 32].into());
assert!(v == vec![(4u8, [4u8; 32].into()), (12u8, [8u8; 32].into()), (42u8, [42u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(12u8, [8u8; 32].into()),
(42u8, [42u8; 32].into())
]
);
intermediate_set_child(&mut v, 6u8, [6u8; 32].into());
assert!(v == vec![(4u8, [4u8; 32].into()), (6u8, [6u8; 32].into()), (12u8, [8u8; 32].into()), (42u8, [42u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(6u8, [6u8; 32].into()),
(12u8, [8u8; 32].into()),
(42u8, [42u8; 32].into())
]
);
intermediate_rm_child(&mut v, 42u8);
assert!(v == vec![(4u8, [4u8; 32].into()), (6u8, [6u8; 32].into()), (12u8, [8u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(6u8, [6u8; 32].into()),
(12u8, [8u8; 32].into())
]
);
intermediate_rm_child(&mut v, 11u8);
assert!(v == vec![(4u8, [4u8; 32].into()), (6u8, [6u8; 32].into()), (12u8, [8u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(6u8, [6u8; 32].into()),
(12u8, [8u8; 32].into())
]
);
intermediate_rm_child(&mut v, 6u8);
assert!(v == vec![(4u8, [4u8; 32].into()), (12u8, [8u8; 32].into())]);
assert_eq!(v, vec![(4u8, [4u8; 32].into()), (12u8, [8u8; 32].into())]);
intermediate_set_child(&mut v, 6u8, [7u8; 32].into());
assert!(v == vec![(4u8, [4u8; 32].into()), (6u8, [7u8; 32].into()), (12u8, [8u8; 32].into())]);
assert_eq!(
v,
vec![
(4u8, [4u8; 32].into()),
(6u8, [7u8; 32].into()),
(12u8, [8u8; 32].into())
]
);
}

View file

@ -53,7 +53,6 @@ impl TableReplication for TableFullReplication {
fn split_points(&self, _ring: &Ring) -> Vec<Hash> {
let mut ret = vec![];
ret.push([0u8; 32].into());
ret.push([0xFFu8; 32].into());
ret
}
}

View file

@ -44,11 +44,13 @@ impl TableReplication for TableShardedReplication {
fn split_points(&self, ring: &Ring) -> Vec<Hash> {
let mut ret = vec![];
ret.push([0u8; 32].into());
for entry in ring.ring.iter() {
ret.push(entry.location);
}
ret.push([0xFFu8; 32].into());
if ret.len() > 0 {
assert_eq!(ret[0], [0u8; 32].into());
}
ret
}
}

632
src/table/sync.rs Normal file
View file

@ -0,0 +1,632 @@
use std::collections::VecDeque;
use std::convert::TryInto;
use std::sync::{Arc, Mutex};
use std::time::{Duration, Instant};
use futures::future::join_all;
use futures::{pin_mut, select};
use futures_util::future::*;
use futures_util::stream::*;
use rand::Rng;
use serde::{Deserialize, Serialize};
use serde_bytes::ByteBuf;
use tokio::sync::{mpsc, watch};
use garage_rpc::ring::Ring;
use garage_util::data::*;
use garage_util::error::Error;
use crate::data::*;
use crate::merkle::*;
use crate::replication::*;
use crate::*;
const TABLE_SYNC_RPC_TIMEOUT: Duration = Duration::from_secs(30);
// Do anti-entropy every 10 minutes
const ANTI_ENTROPY_INTERVAL: Duration = Duration::from_secs(10 * 60);
pub struct TableSyncer<F: TableSchema, R: TableReplication> {
data: Arc<TableData<F>>,
aux: Arc<TableAux<F, R>>,
todo: Mutex<SyncTodo>,
}
type RootCk = Vec<(MerklePartition, Hash)>;
#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
pub struct PartitionRange {
begin: MerklePartition,
// if end is None, go all the way to partition 0xFFFF included
end: Option<MerklePartition>,
}
#[derive(Serialize, Deserialize)]
pub(crate) enum SyncRPC {
RootCkHash(PartitionRange, Hash),
RootCkList(PartitionRange, RootCk),
CkNoDifference,
GetNode(MerkleNodeKey),
Node(MerkleNodeKey, MerkleNode),
Items(Vec<Arc<ByteBuf>>),
}
struct SyncTodo {
todo: Vec<TodoPartition>,
}
#[derive(Debug, Clone)]
struct TodoPartition {
range: PartitionRange,
// Are we a node that stores this partition or not?
retain: bool,
}
impl<F, R> TableSyncer<F, R>
where
F: TableSchema + 'static,
R: TableReplication + 'static,
{
pub(crate) fn launch(data: Arc<TableData<F>>, aux: Arc<TableAux<F, R>>) -> Arc<Self> {
let todo = SyncTodo { todo: vec![] };
let syncer = Arc::new(Self {
data: data.clone(),
aux: aux.clone(),
todo: Mutex::new(todo),
});
let (busy_tx, busy_rx) = mpsc::unbounded_channel();
let s1 = syncer.clone();
aux.system.background.spawn_worker(
format!("table sync watcher for {}", data.name),
move |must_exit: watch::Receiver<bool>| s1.watcher_task(must_exit, busy_rx),
);
let s2 = syncer.clone();
aux.system.background.spawn_worker(
format!("table syncer for {}", data.name),
move |must_exit: watch::Receiver<bool>| s2.syncer_task(must_exit, busy_tx),
);
let s3 = syncer.clone();
tokio::spawn(async move {
tokio::time::delay_for(Duration::from_secs(20)).await;
s3.add_full_sync();
});
syncer
}
async fn watcher_task(
self: Arc<Self>,
mut must_exit: watch::Receiver<bool>,
mut busy_rx: mpsc::UnboundedReceiver<bool>,
) -> Result<(), Error> {
let mut ring_recv: watch::Receiver<Arc<Ring>> = self.aux.system.ring.clone();
let mut nothing_to_do_since = Some(Instant::now());
while !*must_exit.borrow() {
let s_ring_recv = ring_recv.recv().fuse();
let s_busy = busy_rx.recv().fuse();
let s_must_exit = must_exit.recv().fuse();
let s_timeout = tokio::time::delay_for(Duration::from_secs(1)).fuse();
pin_mut!(s_ring_recv, s_busy, s_must_exit, s_timeout);
select! {
new_ring_r = s_ring_recv => {
if new_ring_r.is_some() {
debug!("({}) Adding ring difference to syncer todo list", self.data.name);
self.add_full_sync();
}
}
busy_opt = s_busy => {
if let Some(busy) = busy_opt {
if busy {
nothing_to_do_since = None;
} else {
if nothing_to_do_since.is_none() {
nothing_to_do_since = Some(Instant::now());
}
}
}
}
must_exit_v = s_must_exit => {
if must_exit_v.unwrap_or(false) {
break;
}
}
_ = s_timeout => {
if nothing_to_do_since.map(|t| Instant::now() - t >= ANTI_ENTROPY_INTERVAL).unwrap_or(false) {
nothing_to_do_since = None;
debug!("({}) Adding full sync to syncer todo list", self.data.name);
self.add_full_sync();
}
}
}
}
Ok(())
}
pub fn add_full_sync(&self) {
self.todo
.lock()
.unwrap()
.add_full_sync(&self.data, &self.aux);
}
async fn syncer_task(
self: Arc<Self>,
mut must_exit: watch::Receiver<bool>,
busy_tx: mpsc::UnboundedSender<bool>,
) -> Result<(), Error> {
while !*must_exit.borrow() {
let task = self.todo.lock().unwrap().pop_task();
if let Some(partition) = task {
busy_tx.send(true)?;
let res = self
.clone()
.sync_partition(&partition, &mut must_exit)
.await;
if let Err(e) = res {
warn!(
"({}) Error while syncing {:?}: {}",
self.data.name, partition, e
);
}
} else {
busy_tx.send(false)?;
tokio::time::delay_for(Duration::from_secs(1)).await;
}
}
Ok(())
}
async fn sync_partition(
self: Arc<Self>,
partition: &TodoPartition,
must_exit: &mut watch::Receiver<bool>,
) -> Result<(), Error> {
if partition.retain {
let my_id = self.aux.system.id;
let nodes = self
.aux
.replication
.write_nodes(
&hash_of_merkle_partition(partition.range.begin),
&self.aux.system,
)
.into_iter()
.filter(|node| *node != my_id)
.collect::<Vec<_>>();
debug!(
"({}) Syncing {:?} with {:?}...",
self.data.name, partition, nodes
);
let mut sync_futures = nodes
.iter()
.map(|node| {
self.clone()
.do_sync_with(partition.clone(), *node, must_exit.clone())
})
.collect::<FuturesUnordered<_>>();
let mut n_errors = 0;
while let Some(r) = sync_futures.next().await {
if let Err(e) = r {
n_errors += 1;
warn!("({}) Sync error: {}", self.data.name, e);
}
}
if n_errors > self.aux.replication.max_write_errors() {
return Err(Error::Message(format!(
"Sync failed with too many nodes (should have been: {:?}).",
nodes
)));
}
} else {
self.offload_partition(
&hash_of_merkle_partition(partition.range.begin),
&hash_of_merkle_partition_opt(partition.range.end),
must_exit,
)
.await?;
}
Ok(())
}
// Offload partition: this partition is not something we are storing,
// so send it out to all other nodes that store it and delete items locally.
// We don't bother checking if the remote nodes already have the items,
// we just batch-send everything. Offloading isn't supposed to happen very often.
// If any of the nodes that are supposed to store the items is unable to
// save them, we interrupt the process.
async fn offload_partition(
self: &Arc<Self>,
begin: &Hash,
end: &Hash,
must_exit: &mut watch::Receiver<bool>,
) -> Result<(), Error> {
let mut counter: usize = 0;
while !*must_exit.borrow() {
let mut items = Vec::new();
for item in self.data.store.range(begin.to_vec()..end.to_vec()) {
let (key, value) = item?;
items.push((key.to_vec(), Arc::new(ByteBuf::from(value.as_ref()))));
if items.len() >= 1024 {
break;
}
}
if items.len() > 0 {
let nodes = self
.aux
.replication
.write_nodes(&begin, &self.aux.system)
.into_iter()
.collect::<Vec<_>>();
if nodes.contains(&self.aux.system.id) {
warn!("Interrupting offload as partitions seem to have changed");
break;
}
counter += 1;
debug!(
"Offloading {} items from {:?}..{:?} ({})",
items.len(),
begin,
end,
counter
);
self.offload_items(&items, &nodes[..]).await?;
} else {
break;
}
}
Ok(())
}
async fn offload_items(
self: &Arc<Self>,
items: &Vec<(Vec<u8>, Arc<ByteBuf>)>,
nodes: &[UUID],
) -> Result<(), Error> {
let values = items.iter().map(|(_k, v)| v.clone()).collect::<Vec<_>>();
let update_msg = Arc::new(TableRPC::<F>::Update(values));
for res in join_all(nodes.iter().map(|to| {
self.aux
.rpc_client
.call_arc(*to, update_msg.clone(), TABLE_SYNC_RPC_TIMEOUT)
}))
.await
{
res?;
}
// All remote nodes have written those items, now we can delete them locally
let mut not_removed = 0;
for (k, v) in items.iter() {
if !self.data.delete_if_equal(&k[..], &v[..])? {
not_removed += 1;
}
}
if not_removed > 0 {
debug!("{} items not removed during offload because they changed in between (trying again...)", not_removed);
}
Ok(())
}
// ======= SYNCHRONIZATION PROCEDURE -- DRIVER SIDE ======
fn get_root_ck(&self, range: PartitionRange) -> Result<RootCk, Error> {
let begin = u16::from_be_bytes(range.begin);
let range_iter = match range.end {
Some(end) => {
let end = u16::from_be_bytes(end);
begin..=(end - 1)
}
None => begin..=0xFFFF,
};
let mut ret = vec![];
for i in range_iter {
let key = MerkleNodeKey {
partition: u16::to_be_bytes(i),
prefix: vec![],
};
match self.data.merkle_updater.read_node(&key)? {
MerkleNode::Empty => (),
x => {
ret.push((key.partition, hash_of(&x)?));
}
}
}
Ok(ret)
}
async fn do_sync_with(
self: Arc<Self>,
partition: TodoPartition,
who: UUID,
must_exit: watch::Receiver<bool>,
) -> Result<(), Error> {
let root_ck = self.get_root_ck(partition.range)?;
let root_ck_hash = hash_of(&root_ck)?;
// If their root checksum has level > than us, use that as a reference
let root_resp = self
.aux
.rpc_client
.call(
who,
TableRPC::<F>::SyncRPC(SyncRPC::RootCkHash(partition.range, root_ck_hash)),
TABLE_SYNC_RPC_TIMEOUT,
)
.await?;
let mut todo = match root_resp {
TableRPC::<F>::SyncRPC(SyncRPC::CkNoDifference) => {
debug!(
"({}) Sync {:?} with {:?}: no difference",
self.data.name, partition, who
);
return Ok(());
}
TableRPC::<F>::SyncRPC(SyncRPC::RootCkList(_, their_root_ck)) => {
let join = join_ordered(&root_ck[..], &their_root_ck[..]);
let mut todo = VecDeque::new();
for (p, v1, v2) in join.iter() {
let diff = match (v1, v2) {
(Some(_), None) | (None, Some(_)) => true,
(Some(a), Some(b)) => a != b,
_ => false,
};
if diff {
todo.push_back(MerkleNodeKey {
partition: **p,
prefix: vec![],
});
}
}
debug!(
"({}) Sync {:?} with {:?}: todo.len() = {}",
self.data.name,
partition,
who,
todo.len()
);
todo
}
x => {
return Err(Error::Message(format!(
"Invalid respone to RootCkHash RPC: {}",
debug_serialize(x)
)));
}
};
let mut todo_items = vec![];
while !todo.is_empty() && !*must_exit.borrow() {
let key = todo.pop_front().unwrap();
let node = self.data.merkle_updater.read_node(&key)?;
match node {
MerkleNode::Empty => {
// They have items we don't have.
// We don't request those items from them, they will send them.
// We only bother with pushing items that differ
}
MerkleNode::Leaf(ik, _) => {
// Just send that item directly
if let Some(val) = self.data.store.get(ik)? {
todo_items.push(val.to_vec());
}
}
MerkleNode::Intermediate(l) => {
let remote_node = match self
.aux
.rpc_client
.call(
who,
TableRPC::<F>::SyncRPC(SyncRPC::GetNode(key.clone())),
TABLE_SYNC_RPC_TIMEOUT,
)
.await?
{
TableRPC::<F>::SyncRPC(SyncRPC::Node(_, node)) => node,
x => {
return Err(Error::Message(format!(
"Invalid respone to GetNode RPC: {}",
debug_serialize(x)
)));
}
};
let int_l2 = match remote_node {
MerkleNode::Intermediate(l2) => l2,
_ => vec![],
};
let join = join_ordered(&l[..], &int_l2[..]);
for (p, v1, v2) in join.into_iter() {
let diff = match (v1, v2) {
(Some(_), None) | (None, Some(_)) => true,
(Some(a), Some(b)) => a != b,
_ => false,
};
if diff {
todo.push_back(key.add_byte(*p));
}
}
}
}
if todo_items.len() >= 256 {
self.send_items(who, std::mem::replace(&mut todo_items, vec![]))
.await?;
}
}
if !todo_items.is_empty() {
self.send_items(who, todo_items).await?;
}
Ok(())
}
async fn send_items(&self, who: UUID, item_list: Vec<Vec<u8>>) -> Result<(), Error> {
info!(
"({}) Sending {} items to {:?}",
self.data.name,
item_list.len(),
who
);
let mut values = vec![];
for item in item_list.iter() {
if let Some(v) = self.data.store.get(&item[..])? {
values.push(Arc::new(ByteBuf::from(v.as_ref())));
}
}
let rpc_resp = self
.aux
.rpc_client
.call(who, TableRPC::<F>::Update(values), TABLE_SYNC_RPC_TIMEOUT)
.await?;
if let TableRPC::<F>::Ok = rpc_resp {
Ok(())
} else {
Err(Error::Message(format!(
"Unexpected response to RPC Update: {}",
debug_serialize(&rpc_resp)
)))
}
}
// ======= SYNCHRONIZATION PROCEDURE -- RECEIVER SIDE ======
pub(crate) async fn handle_rpc(self: &Arc<Self>, message: &SyncRPC) -> Result<SyncRPC, Error> {
match message {
SyncRPC::RootCkHash(range, h) => {
let root_ck = self.get_root_ck(*range)?;
let hash = hash_of(&root_ck)?;
if hash == *h {
Ok(SyncRPC::CkNoDifference)
} else {
Ok(SyncRPC::RootCkList(*range, root_ck))
}
}
SyncRPC::GetNode(k) => {
let node = self.data.merkle_updater.read_node(&k)?;
Ok(SyncRPC::Node(k.clone(), node))
}
_ => Err(Error::Message(format!("Unexpected sync RPC"))),
}
}
}
impl SyncTodo {
fn add_full_sync<F: TableSchema, R: TableReplication>(
&mut self,
data: &TableData<F>,
aux: &TableAux<F, R>,
) {
let my_id = aux.system.id;
self.todo.clear();
let ring = aux.system.ring.borrow().clone();
let split_points = aux.replication.split_points(&ring);
for i in 0..split_points.len() {
let begin: MerklePartition = {
let b = split_points[i];
assert_eq!(b.as_slice()[2..], [0u8; 30][..]);
b.as_slice()[..2].try_into().unwrap()
};
let end: Option<MerklePartition> = if i + 1 < split_points.len() {
let e = split_points[i + 1];
assert_eq!(e.as_slice()[2..], [0u8; 30][..]);
Some(e.as_slice()[..2].try_into().unwrap())
} else {
None
};
let begin_hash = hash_of_merkle_partition(begin);
let end_hash = hash_of_merkle_partition_opt(end);
let nodes = aux.replication.replication_nodes(&begin_hash, &ring);
let retain = nodes.contains(&my_id);
if !retain {
// Check if we have some data to send, otherwise skip
if data.store.range(begin_hash..end_hash).next().is_none() {
continue;
}
}
self.todo.push(TodoPartition {
range: PartitionRange { begin, end },
retain,
});
}
}
fn pop_task(&mut self) -> Option<TodoPartition> {
if self.todo.is_empty() {
return None;
}
let i = rand::thread_rng().gen_range::<usize, _, _>(0, self.todo.len());
if i == self.todo.len() - 1 {
self.todo.pop()
} else {
let replacement = self.todo.pop().unwrap();
let ret = std::mem::replace(&mut self.todo[i], replacement);
Some(ret)
}
}
}
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>(
x: &'a [(K, V1)],
y: &'a [(K, V2)],
) -> Vec<(&'a K, Option<&'a V1>, Option<&'a V2>)> {
let mut ret = vec![];
let mut i = 0;
let mut j = 0;
while i < x.len() || j < y.len() {
if i < x.len() && j < y.len() && x[i].0 == y[j].0 {
ret.push((&x[i].0, Some(&x[i].1), Some(&y[j].1)));
i += 1;
j += 1;
} else if i < x.len() && (j == y.len() || x[i].0 < y[j].0) {
ret.push((&x[i].0, Some(&x[i].1), None));
i += 1;
} else if j < y.len() && (i == x.len() || x[i].0 > y[j].0) {
ret.push((&x[i].0, None, Some(&y[j].1)));
j += 1;
} else {
unreachable!();
}
}
ret
}

View file

@ -15,9 +15,9 @@ use garage_rpc::rpc_server::*;
use crate::crdt::CRDT;
use crate::data::*;
use crate::schema::*;
use crate::table_sync::*;
use crate::replication::*;
use crate::schema::*;
use crate::sync::*;
const TABLE_RPC_TIMEOUT: Duration = Duration::from_secs(10);
@ -50,7 +50,6 @@ pub(crate) enum TableRPC<F: TableSchema> {
impl<F: TableSchema> RpcMessage for TableRPC<F> {}
impl<F, R> Table<F, R>
where
F: TableSchema + 'static,
@ -69,12 +68,7 @@ where
let rpc_path = format!("table_{}", name);
let rpc_client = system.rpc_client::<TableRPC<F>>(&rpc_path);
let data = TableData::new(
name,
instance,
db,
system.background.clone(),
);
let data = TableData::new(name, instance, db, system.background.clone());
let aux = Arc::new(TableAux {
system,
@ -82,16 +76,9 @@ where
rpc_client,
});
let syncer = TableSyncer::launch(
data.clone(),
aux.clone(),
);
let syncer = TableSyncer::launch(data.clone(), aux.clone());
let table = Arc::new(Self {
data,
aux,
syncer,
});
let table = Arc::new(Self { data, aux, syncer });
table.clone().register_handler(rpc_server, rpc_path);
@ -106,7 +93,8 @@ where
let e_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(e)?));
let rpc = TableRPC::<F>::Update(vec![e_enc]);
self.aux.rpc_client
self.aux
.rpc_client
.try_call_many(
&who[..],
rpc,
@ -135,7 +123,11 @@ where
let call_futures = call_list.drain().map(|(node, entries)| async move {
let rpc = TableRPC::<F>::Update(entries);
let resp = self.aux.rpc_client.call(node, rpc, TABLE_RPC_TIMEOUT).await?;
let resp = self
.aux
.rpc_client
.call(node, rpc, TABLE_RPC_TIMEOUT)
.await?;
Ok::<_, Error>((node, resp))
});
let mut resps = call_futures.collect::<FuturesUnordered<_>>();
@ -200,7 +192,8 @@ where
if not_all_same {
let self2 = self.clone();
let ent2 = ret_entry.clone();
self.aux.system
self.aux
.system
.background
.spawn_cancellable(async move { self2.repair_on_read(&who[..], ent2).await });
}
@ -221,7 +214,8 @@ where
let rpc = TableRPC::<F>::ReadRange(partition_key.clone(), begin_sort_key, filter, limit);
let resps = self
.aux.rpc_client
.aux
.rpc_client
.try_call_many(
&who[..],
rpc,
@ -276,7 +270,8 @@ where
async fn repair_on_read(&self, who: &[UUID], what: F::E) -> Result<(), Error> {
let what_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(&what)?));
self.aux.rpc_client
self.aux
.rpc_client
.try_call_many(
&who[..],
TableRPC::<F>::Update(vec![what_enc]),
@ -296,7 +291,8 @@ where
});
let self2 = self.clone();
self.aux.rpc_client
self.aux
.rpc_client
.set_local_handler(self.aux.system.id, move |msg| {
let self2 = self2.clone();
async move { self2.handle(&msg).await }
@ -318,9 +314,7 @@ where
Ok(TableRPC::Ok)
}
TableRPC::SyncRPC(rpc) => {
let response = self.syncer
.handle_rpc(rpc, self.aux.system.background.stop_signal.clone())
.await?;
let response = self.syncer.handle_rpc(rpc).await?;
Ok(TableRPC::SyncRPC(response))
}
_ => Err(Error::BadRPC(format!("Unexpected table RPC"))),

View file

@ -1,898 +0,0 @@
use rand::Rng;
use std::collections::{BTreeMap, VecDeque};
use std::sync::{Arc, Mutex};
use std::time::{Duration, Instant};
use futures::future::join_all;
use futures::{pin_mut, select};
use futures_util::future::*;
use futures_util::stream::*;
use serde::{Deserialize, Serialize};
use serde_bytes::ByteBuf;
use tokio::sync::{mpsc, watch};
use garage_rpc::ring::Ring;
use garage_util::data::*;
use garage_util::error::Error;
use crate::*;
use crate::data::*;
use crate::replication::*;
const MAX_DEPTH: usize = 16;
const TABLE_SYNC_RPC_TIMEOUT: Duration = Duration::from_secs(30);
// Do anti-entropy every 10 minutes
const SCAN_INTERVAL: Duration = Duration::from_secs(10 * 60);
const CHECKSUM_CACHE_TIMEOUT: Duration = Duration::from_secs(10 * 60);
pub struct TableSyncer<F: TableSchema, R: TableReplication> {
data: Arc<TableData<F>>,
aux: Arc<TableAux<F, R>>,
todo: Mutex<SyncTodo>,
cache: Vec<Mutex<BTreeMap<SyncRange, RangeChecksumCache>>>,
}
#[derive(Serialize, Deserialize)]
pub(crate) enum SyncRPC {
GetRootChecksumRange(Hash, Hash),
RootChecksumRange(SyncRange),
Checksums(Vec<RangeChecksum>),
Difference(Vec<SyncRange>, Vec<Arc<ByteBuf>>),
}
struct SyncTodo {
todo: Vec<TodoPartition>,
}
#[derive(Debug, Clone)]
struct TodoPartition {
// Partition consists in hashes between begin included and end excluded
begin: Hash,
end: Hash,
// Are we a node that stores this partition or not?
retain: bool,
}
// A SyncRange defines a query on the dataset stored by a node, in the following way:
// - all items whose key are >= `begin`
// - stopping at the first item whose key hash has at least `level` leading zero bytes (excluded)
// - except if the first item of the range has such many leading zero bytes
// - and stopping at `end` (excluded) if such an item is not found
// The checksum itself does not store all of the items in the database, only the hashes of the "sub-ranges"
// i.e. of ranges of level `level-1` that cover the same range
// (ranges of level 0 do not exist and their hash is simply the hash of the first item >= begin)
// See RangeChecksum for the struct that stores this information.
#[derive(Hash, PartialEq, Eq, Debug, Clone, Serialize, Deserialize)]
pub(crate) struct SyncRange {
begin: Vec<u8>,
end: Vec<u8>,
level: usize,
}
impl std::cmp::PartialOrd for SyncRange {
fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
Some(self.cmp(other))
}
}
impl std::cmp::Ord for SyncRange {
fn cmp(&self, other: &Self) -> std::cmp::Ordering {
self.begin
.cmp(&other.begin)
.then(self.level.cmp(&other.level))
.then(self.end.cmp(&other.end))
}
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub(crate) struct RangeChecksum {
bounds: SyncRange,
children: Vec<(SyncRange, Hash)>,
found_limit: Option<Vec<u8>>,
#[serde(skip, default = "std::time::Instant::now")]
time: Instant,
}
#[derive(Debug, Clone)]
struct RangeChecksumCache {
hash: Option<Hash>, // None if no children
found_limit: Option<Vec<u8>>,
time: Instant,
}
impl<F, R> TableSyncer<F, R>
where
F: TableSchema + 'static,
R: TableReplication + 'static,
{
pub(crate) fn launch(data: Arc<TableData<F>>,
aux: Arc<TableAux<F, R>>) -> Arc<Self> {
let todo = SyncTodo{ todo: vec![] };
let syncer = Arc::new(Self {
data: data.clone(),
aux: aux.clone(),
todo: Mutex::new(todo),
cache: (0..MAX_DEPTH)
.map(|_| Mutex::new(BTreeMap::new()))
.collect::<Vec<_>>(),
});
let (busy_tx, busy_rx) = mpsc::unbounded_channel();
let s1 = syncer.clone();
aux.system.background.spawn_worker(
format!("table sync watcher for {}", data.name),
move |must_exit: watch::Receiver<bool>| s1.watcher_task(must_exit, busy_rx),
);
let s2 = syncer.clone();
aux.system.background.spawn_worker(
format!("table syncer for {}", data.name),
move |must_exit: watch::Receiver<bool>| s2.syncer_task(must_exit, busy_tx),
);
let s3 = syncer.clone();
tokio::spawn(async move {
tokio::time::delay_for(Duration::from_secs(20)).await;
s3.add_full_scan();
});
syncer
}
async fn watcher_task(
self: Arc<Self>,
mut must_exit: watch::Receiver<bool>,
mut busy_rx: mpsc::UnboundedReceiver<bool>,
) -> Result<(), Error> {
let mut prev_ring: Arc<Ring> = self.aux.system.ring.borrow().clone();
let mut ring_recv: watch::Receiver<Arc<Ring>> = self.aux.system.ring.clone();
let mut nothing_to_do_since = Some(Instant::now());
while !*must_exit.borrow() {
let s_ring_recv = ring_recv.recv().fuse();
let s_busy = busy_rx.recv().fuse();
let s_must_exit = must_exit.recv().fuse();
let s_timeout = tokio::time::delay_for(Duration::from_secs(1)).fuse();
pin_mut!(s_ring_recv, s_busy, s_must_exit, s_timeout);
select! {
new_ring_r = s_ring_recv => {
if let Some(new_ring) = new_ring_r {
debug!("({}) Adding ring difference to syncer todo list", self.data.name);
self.todo.lock().unwrap().add_ring_difference(&prev_ring, &new_ring, &self.data, &self.aux);
prev_ring = new_ring;
}
}
busy_opt = s_busy => {
if let Some(busy) = busy_opt {
if busy {
nothing_to_do_since = None;
} else {
if nothing_to_do_since.is_none() {
nothing_to_do_since = Some(Instant::now());
}
}
}
}
must_exit_v = s_must_exit => {
if must_exit_v.unwrap_or(false) {
break;
}
}
_ = s_timeout => {
if nothing_to_do_since.map(|t| Instant::now() - t >= SCAN_INTERVAL).unwrap_or(false) {
nothing_to_do_since = None;
debug!("({}) Adding full scan to syncer todo list", self.data.name);
self.add_full_scan();
}
}
}
}
Ok(())
}
pub fn add_full_scan(&self) {
self.todo.lock().unwrap().add_full_scan(&self.data, &self.aux);
}
async fn syncer_task(
self: Arc<Self>,
mut must_exit: watch::Receiver<bool>,
busy_tx: mpsc::UnboundedSender<bool>,
) -> Result<(), Error> {
while !*must_exit.borrow() {
let task = self.todo.lock().unwrap().pop_task();
if let Some(partition) = task {
busy_tx.send(true)?;
let res = self
.clone()
.sync_partition(&partition, &mut must_exit)
.await;
if let Err(e) = res {
warn!(
"({}) Error while syncing {:?}: {}",
self.data.name, partition, e
);
}
} else {
busy_tx.send(false)?;
tokio::time::delay_for(Duration::from_secs(1)).await;
}
}
Ok(())
}
async fn sync_partition(
self: Arc<Self>,
partition: &TodoPartition,
must_exit: &mut watch::Receiver<bool>,
) -> Result<(), Error> {
if partition.retain {
let my_id = self.aux.system.id;
let nodes = self
.aux
.replication
.write_nodes(&partition.begin, &self.aux.system)
.into_iter()
.filter(|node| *node != my_id)
.collect::<Vec<_>>();
debug!(
"({}) Preparing to sync {:?} with {:?}...",
self.data.name, partition, nodes
);
let root_cks = self.root_checksum(&partition.begin, &partition.end, must_exit)?;
let mut sync_futures = nodes
.iter()
.map(|node| {
self.clone().do_sync_with(
partition.clone(),
root_cks.clone(),
*node,
must_exit.clone(),
)
})
.collect::<FuturesUnordered<_>>();
let mut n_errors = 0;
while let Some(r) = sync_futures.next().await {
if let Err(e) = r {
n_errors += 1;
warn!("({}) Sync error: {}", self.data.name, e);
}
}
if n_errors > self.aux.replication.max_write_errors() {
return Err(Error::Message(format!(
"Sync failed with too many nodes (should have been: {:?}).",
nodes
)));
}
} else {
self.offload_partition(&partition.begin, &partition.end, must_exit)
.await?;
}
Ok(())
}
// Offload partition: this partition is not something we are storing,
// so send it out to all other nodes that store it and delete items locally.
// We don't bother checking if the remote nodes already have the items,
// we just batch-send everything. Offloading isn't supposed to happen very often.
// If any of the nodes that are supposed to store the items is unable to
// save them, we interrupt the process.
async fn offload_partition(
self: &Arc<Self>,
begin: &Hash,
end: &Hash,
must_exit: &mut watch::Receiver<bool>,
) -> Result<(), Error> {
let mut counter: usize = 0;
while !*must_exit.borrow() {
let mut items = Vec::new();
for item in self.data.store.range(begin.to_vec()..end.to_vec()) {
let (key, value) = item?;
items.push((key.to_vec(), Arc::new(ByteBuf::from(value.as_ref()))));
if items.len() >= 1024 {
break;
}
}
if items.len() > 0 {
let nodes = self
.aux
.replication
.write_nodes(&begin, &self.aux.system)
.into_iter()
.collect::<Vec<_>>();
if nodes.contains(&self.aux.system.id) {
warn!("Interrupting offload as partitions seem to have changed");
break;
}
counter += 1;
debug!(
"Offloading {} items from {:?}..{:?} ({})",
items.len(),
begin,
end,
counter
);
self.offload_items(&items, &nodes[..]).await?;
} else {
break;
}
}
Ok(())
}
async fn offload_items(
self: &Arc<Self>,
items: &Vec<(Vec<u8>, Arc<ByteBuf>)>,
nodes: &[UUID],
) -> Result<(), Error> {
let values = items.iter().map(|(_k, v)| v.clone()).collect::<Vec<_>>();
let update_msg = Arc::new(TableRPC::<F>::Update(values));
for res in join_all(nodes.iter().map(|to| {
self.aux
.rpc_client
.call_arc(*to, update_msg.clone(), TABLE_SYNC_RPC_TIMEOUT)
}))
.await
{
res?;
}
// All remote nodes have written those items, now we can delete them locally
let mut not_removed = 0;
for (k, v) in items.iter() {
if !self.data.delete_if_equal(&k[..], &v[..])? {
not_removed += 1;
}
}
if not_removed > 0 {
debug!("{} items not removed during offload because they changed in between (trying again...)", not_removed);
}
Ok(())
}
fn root_checksum(
self: &Arc<Self>,
begin: &Hash,
end: &Hash,
must_exit: &mut watch::Receiver<bool>,
) -> Result<RangeChecksum, Error> {
for i in 1..MAX_DEPTH {
let rc = self.range_checksum(
&SyncRange {
begin: begin.to_vec(),
end: end.to_vec(),
level: i,
},
must_exit,
)?;
if rc.found_limit.is_none() {
return Ok(rc);
}
}
Err(Error::Message(format!(
"Unable to compute root checksum (this should never happen)"
)))
}
fn range_checksum(
self: &Arc<Self>,
range: &SyncRange,
must_exit: &mut watch::Receiver<bool>,
) -> Result<RangeChecksum, Error> {
assert!(range.level != 0);
trace!("Call range_checksum {:?}", range);
if range.level == 1 {
let mut children = vec![];
for item in self
.data
.store
.range(range.begin.clone()..range.end.clone())
{
let (key, value) = item?;
let key_hash = blake2sum(&key[..]);
if children.len() > 0
&& key_hash.as_slice()[0..range.level]
.iter()
.all(|x| *x == 0u8)
{
trace!(
"range_checksum {:?} returning {} items",
range,
children.len()
);
return Ok(RangeChecksum {
bounds: range.clone(),
children,
found_limit: Some(key.to_vec()),
time: Instant::now(),
});
}
let item_range = SyncRange {
begin: key.to_vec(),
end: vec![],
level: 0,
};
children.push((item_range, blake2sum(&value[..])));
}
trace!(
"range_checksum {:?} returning {} items",
range,
children.len()
);
Ok(RangeChecksum {
bounds: range.clone(),
children,
found_limit: None,
time: Instant::now(),
})
} else {
let mut children = vec![];
let mut sub_range = SyncRange {
begin: range.begin.clone(),
end: range.end.clone(),
level: range.level - 1,
};
let mut time = Instant::now();
while !*must_exit.borrow() {
let sub_ck = self.range_checksum_cached_hash(&sub_range, must_exit)?;
if let Some(hash) = sub_ck.hash {
children.push((sub_range.clone(), hash));
if sub_ck.time < time {
time = sub_ck.time;
}
}
if sub_ck.found_limit.is_none() || sub_ck.hash.is_none() {
trace!(
"range_checksum {:?} returning {} items",
range,
children.len()
);
return Ok(RangeChecksum {
bounds: range.clone(),
children,
found_limit: None,
time,
});
}
let found_limit = sub_ck.found_limit.unwrap();
let actual_limit_hash = blake2sum(&found_limit[..]);
if actual_limit_hash.as_slice()[0..range.level]
.iter()
.all(|x| *x == 0u8)
{
trace!(
"range_checksum {:?} returning {} items",
range,
children.len()
);
return Ok(RangeChecksum {
bounds: range.clone(),
children,
found_limit: Some(found_limit.clone()),
time,
});
}
sub_range.begin = found_limit;
}
trace!("range_checksum {:?} exiting due to must_exit", range);
Err(Error::Message(format!("Exiting.")))
}
}
fn range_checksum_cached_hash(
self: &Arc<Self>,
range: &SyncRange,
must_exit: &mut watch::Receiver<bool>,
) -> Result<RangeChecksumCache, Error> {
{
let mut cache = self.cache[range.level].lock().unwrap();
if let Some(v) = cache.get(&range) {
if Instant::now() - v.time < CHECKSUM_CACHE_TIMEOUT {
return Ok(v.clone());
}
}
cache.remove(&range);
}
let v = self.range_checksum(&range, must_exit)?;
trace!(
"({}) New checksum calculated for {}-{}/{}, {} children",
self.data.name,
hex::encode(&range.begin)
.chars()
.take(16)
.collect::<String>(),
hex::encode(&range.end).chars().take(16).collect::<String>(),
range.level,
v.children.len()
);
let hash = if v.children.len() > 0 {
Some(blake2sum(&rmp_to_vec_all_named(&v)?[..]))
} else {
None
};
let cache_entry = RangeChecksumCache {
hash,
found_limit: v.found_limit,
time: v.time,
};
let mut cache = self.cache[range.level].lock().unwrap();
cache.insert(range.clone(), cache_entry.clone());
Ok(cache_entry)
}
async fn do_sync_with(
self: Arc<Self>,
partition: TodoPartition,
root_ck: RangeChecksum,
who: UUID,
mut must_exit: watch::Receiver<bool>,
) -> Result<(), Error> {
let mut todo = VecDeque::new();
// If their root checksum has level > than us, use that as a reference
let root_cks_resp = self
.aux
.rpc_client
.call(
who,
TableRPC::<F>::SyncRPC(SyncRPC::GetRootChecksumRange(
partition.begin.clone(),
partition.end.clone(),
)),
TABLE_SYNC_RPC_TIMEOUT,
)
.await?;
if let TableRPC::<F>::SyncRPC(SyncRPC::RootChecksumRange(range)) = root_cks_resp {
if range.level > root_ck.bounds.level {
let their_root_range_ck = self.range_checksum(&range, &mut must_exit)?;
todo.push_back(their_root_range_ck);
} else {
todo.push_back(root_ck);
}
} else {
return Err(Error::Message(format!(
"Invalid respone to GetRootChecksumRange RPC: {}",
debug_serialize(root_cks_resp)
)));
}
while !todo.is_empty() && !*must_exit.borrow() {
let total_children = todo.iter().map(|x| x.children.len()).fold(0, |x, y| x + y);
trace!(
"({}) Sync with {:?}: {} ({}) remaining",
self.data.name,
who,
todo.len(),
total_children
);
let step_size = std::cmp::min(16, todo.len());
let step = todo.drain(..step_size).collect::<Vec<_>>();
let rpc_resp = self
.aux
.rpc_client
.call(
who,
TableRPC::<F>::SyncRPC(SyncRPC::Checksums(step)),
TABLE_SYNC_RPC_TIMEOUT,
)
.await?;
if let TableRPC::<F>::SyncRPC(SyncRPC::Difference(mut diff_ranges, diff_items)) =
rpc_resp
{
if diff_ranges.len() > 0 || diff_items.len() > 0 {
info!(
"({}) Sync with {:?}: difference {} ranges, {} items",
self.data.name,
who,
diff_ranges.len(),
diff_items.len()
);
}
let mut items_to_send = vec![];
for differing in diff_ranges.drain(..) {
if differing.level == 0 {
items_to_send.push(differing.begin);
} else {
let checksum = self.range_checksum(&differing, &mut must_exit)?;
todo.push_back(checksum);
}
}
if diff_items.len() > 0 {
self.data.update_many(&diff_items[..])?;
}
if items_to_send.len() > 0 {
self.send_items(who, items_to_send).await?;
}
} else {
return Err(Error::Message(format!(
"Unexpected response to sync RPC checksums: {}",
debug_serialize(&rpc_resp)
)));
}
}
Ok(())
}
async fn send_items(&self, who: UUID, item_list: Vec<Vec<u8>>) -> Result<(), Error> {
info!(
"({}) Sending {} items to {:?}",
self.data.name,
item_list.len(),
who
);
let mut values = vec![];
for item in item_list.iter() {
if let Some(v) = self.data.store.get(&item[..])? {
values.push(Arc::new(ByteBuf::from(v.as_ref())));
}
}
let rpc_resp = self
.aux
.rpc_client
.call(who, TableRPC::<F>::Update(values), TABLE_SYNC_RPC_TIMEOUT)
.await?;
if let TableRPC::<F>::Ok = rpc_resp {
Ok(())
} else {
Err(Error::Message(format!(
"Unexpected response to RPC Update: {}",
debug_serialize(&rpc_resp)
)))
}
}
pub(crate) async fn handle_rpc(
self: &Arc<Self>,
message: &SyncRPC,
mut must_exit: watch::Receiver<bool>,
) -> Result<SyncRPC, Error> {
match message {
SyncRPC::GetRootChecksumRange(begin, end) => {
let root_cks = self.root_checksum(&begin, &end, &mut must_exit)?;
Ok(SyncRPC::RootChecksumRange(root_cks.bounds))
}
SyncRPC::Checksums(checksums) => {
self.handle_checksums_rpc(&checksums[..], &mut must_exit)
.await
}
_ => Err(Error::Message(format!("Unexpected sync RPC"))),
}
}
async fn handle_checksums_rpc(
self: &Arc<Self>,
checksums: &[RangeChecksum],
must_exit: &mut watch::Receiver<bool>,
) -> Result<SyncRPC, Error> {
let mut ret_ranges = vec![];
let mut ret_items = vec![];
for their_ckr in checksums.iter() {
let our_ckr = self.range_checksum(&their_ckr.bounds, must_exit)?;
for (their_range, their_hash) in their_ckr.children.iter() {
let differs = match our_ckr
.children
.binary_search_by(|(our_range, _)| our_range.cmp(&their_range))
{
Err(_) => {
if their_range.level >= 1 {
let cached_hash =
self.range_checksum_cached_hash(&their_range, must_exit)?;
cached_hash.hash.map(|h| h != *their_hash).unwrap_or(true)
} else {
true
}
}
Ok(i) => our_ckr.children[i].1 != *their_hash,
};
if differs {
ret_ranges.push(their_range.clone());
if their_range.level == 0 {
if let Some(item_bytes) =
self.data.store.get(their_range.begin.as_slice())?
{
ret_items.push(Arc::new(ByteBuf::from(item_bytes.to_vec())));
}
}
}
}
for (our_range, _hash) in our_ckr.children.iter() {
if let Some(their_found_limit) = &their_ckr.found_limit {
if our_range.begin.as_slice() > their_found_limit.as_slice() {
break;
}
}
let not_present = our_ckr
.children
.binary_search_by(|(their_range, _)| their_range.cmp(&our_range))
.is_err();
if not_present {
if our_range.level > 0 {
ret_ranges.push(our_range.clone());
}
if our_range.level == 0 {
if let Some(item_bytes) =
self.data.store.get(our_range.begin.as_slice())?
{
ret_items.push(Arc::new(ByteBuf::from(item_bytes.to_vec())));
}
}
}
}
}
let n_checksums = checksums
.iter()
.map(|x| x.children.len())
.fold(0, |x, y| x + y);
if ret_ranges.len() > 0 || ret_items.len() > 0 {
trace!(
"({}) Checksum comparison RPC: {} different + {} items for {} received",
self.data.name,
ret_ranges.len(),
ret_items.len(),
n_checksums
);
}
Ok(SyncRPC::Difference(ret_ranges, ret_items))
}
pub(crate) fn invalidate(self: &Arc<Self>, item_key: &[u8]) {
for i in 1..MAX_DEPTH {
let needle = SyncRange {
begin: item_key.to_vec(),
end: vec![],
level: i,
};
let mut cache = self.cache[i].lock().unwrap();
if let Some(cache_entry) = cache.range(..=needle).rev().next() {
if cache_entry.0.begin[..] <= *item_key && cache_entry.0.end[..] > *item_key {
let index = cache_entry.0.clone();
drop(cache_entry);
cache.remove(&index);
}
}
}
}
}
impl SyncTodo {
fn add_full_scan<F: TableSchema, R: TableReplication>(&mut self, data: &TableData<F>, aux: &TableAux<F, R>) {
let my_id = aux.system.id;
self.todo.clear();
let ring = aux.system.ring.borrow().clone();
let split_points = aux.replication.split_points(&ring);
for i in 0..split_points.len() - 1 {
let begin = split_points[i];
let end = split_points[i + 1];
if begin == end {
continue;
}
let nodes = aux.replication.replication_nodes(&begin, &ring);
let retain = nodes.contains(&my_id);
if !retain {
// Check if we have some data to send, otherwise skip
if data.store.range(begin..end).next().is_none() {
continue;
}
}
self.todo.push(TodoPartition { begin, end, retain });
}
}
fn add_ring_difference<F: TableSchema, R: TableReplication>(
&mut self,
old_ring: &Ring,
new_ring: &Ring,
data: &TableData<F>, aux: &TableAux<F, R>,
) {
let my_id = aux.system.id;
// If it is us who are entering or leaving the system,
// initiate a full sync instead of incremental sync
if old_ring.config.members.contains_key(&my_id)
!= new_ring.config.members.contains_key(&my_id)
{
self.add_full_scan(data, aux);
return;
}
let mut all_points = None
.into_iter()
.chain(aux.replication.split_points(old_ring).drain(..))
.chain(aux.replication.split_points(new_ring).drain(..))
.chain(self.todo.iter().map(|x| x.begin))
.chain(self.todo.iter().map(|x| x.end))
.collect::<Vec<_>>();
all_points.sort();
all_points.dedup();
let mut old_todo = std::mem::replace(&mut self.todo, vec![]);
old_todo.sort_by(|x, y| x.begin.cmp(&y.begin));
let mut new_todo = vec![];
for i in 0..all_points.len() - 1 {
let begin = all_points[i];
let end = all_points[i + 1];
let was_ours = aux
.replication
.replication_nodes(&begin, &old_ring)
.contains(&my_id);
let is_ours = aux
.replication
.replication_nodes(&begin, &new_ring)
.contains(&my_id);
let was_todo = match old_todo.binary_search_by(|x| x.begin.cmp(&begin)) {
Ok(_) => true,
Err(j) => {
(j > 0 && old_todo[j - 1].begin < end && begin < old_todo[j - 1].end)
|| (j < old_todo.len()
&& old_todo[j].begin < end && begin < old_todo[j].end)
}
};
if was_todo || (is_ours && !was_ours) || (was_ours && !is_ours) {
new_todo.push(TodoPartition {
begin,
end,
retain: is_ours,
});
}
}
self.todo = new_todo;
}
fn pop_task(&mut self) -> Option<TodoPartition> {
if self.todo.is_empty() {
return None;
}
let i = rand::thread_rng().gen_range::<usize, _, _>(0, self.todo.len());
if i == self.todo.len() - 1 {
self.todo.pop()
} else {
let replacement = self.todo.pop().unwrap();
let ret = std::mem::replace(&mut self.todo[i], replacement);
Some(ret)
}
}
}