diff options
Diffstat (limited to 'src/table')
-rw-r--r-- | src/table/Cargo.toml | 2 | ||||
-rw-r--r-- | src/table/data.rs | 3 | ||||
-rw-r--r-- | src/table/gc.rs | 10 | ||||
-rw-r--r-- | src/table/merkle.rs | 2 | ||||
-rw-r--r-- | src/table/replication/fullcopy.rs | 40 | ||||
-rw-r--r-- | src/table/replication/parameters.rs | 29 | ||||
-rw-r--r-- | src/table/replication/sharded.rs | 51 | ||||
-rw-r--r-- | src/table/sync.rs | 249 | ||||
-rw-r--r-- | src/table/table.rs | 159 |
9 files changed, 339 insertions, 206 deletions
diff --git a/src/table/Cargo.toml b/src/table/Cargo.toml index 61b8a82e..cac17da6 100644 --- a/src/table/Cargo.toml +++ b/src/table/Cargo.toml @@ -1,6 +1,6 @@ [package] name = "garage_table" -version = "0.9.3" +version = "0.10.0" authors = ["Alex Auvolat <alex@adnab.me>"] edition = "2018" license = "AGPL-3.0" diff --git a/src/table/data.rs b/src/table/data.rs index bbfdf58b..7f6b7847 100644 --- a/src/table/data.rs +++ b/src/table/data.rs @@ -254,7 +254,8 @@ impl<F: TableSchema, R: TableReplication> TableData<F, R> { // of the GC algorithm, as in all cases GC is suspended if // any node of the partition is unavailable. let pk_hash = Hash::try_from(&tree_key[..32]).unwrap(); - let nodes = self.replication.write_nodes(&pk_hash); + // TODO: this probably breaks when the layout changes + let nodes = self.replication.storage_nodes(&pk_hash); if nodes.first() == Some(&self.system.id) { GcTodoEntry::new(tree_key, new_bytes_hash).save(&self.gc_todo)?; } diff --git a/src/table/gc.rs b/src/table/gc.rs index 5b9124a7..ef788749 100644 --- a/src/table/gc.rs +++ b/src/table/gc.rs @@ -152,7 +152,7 @@ impl<F: TableSchema, R: TableReplication> TableGc<F, R> { let mut partitions = HashMap::new(); for entry in entries { let pkh = Hash::try_from(&entry.key[..32]).unwrap(); - let mut nodes = self.data.replication.write_nodes(&pkh); + let mut nodes = self.data.replication.storage_nodes(&pkh); nodes.retain(|x| *x != self.system.id); nodes.sort(); @@ -227,10 +227,10 @@ impl<F: TableSchema, R: TableReplication> TableGc<F, R> { // GC'ing is not a critical function of the system, so it's not a big // deal if we can't do it right now. self.system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, - &nodes[..], + &nodes, GcRpc::Update(updates), RequestStrategy::with_priority(PRIO_BACKGROUND).with_quorum(nodes.len()), ) @@ -248,10 +248,10 @@ impl<F: TableSchema, R: TableReplication> TableGc<F, R> { // it means that the garbage collection wasn't completed and has // to be retried later. self.system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, - &nodes[..], + &nodes, GcRpc::DeleteIfEqualHash(deletes), RequestStrategy::with_priority(PRIO_BACKGROUND).with_quorum(nodes.len()), ) diff --git a/src/table/merkle.rs b/src/table/merkle.rs index 4577f872..01271c58 100644 --- a/src/table/merkle.rs +++ b/src/table/merkle.rs @@ -13,7 +13,7 @@ use garage_util::data::*; use garage_util::encode::{nonversioned_decode, nonversioned_encode}; use garage_util::error::Error; -use garage_rpc::ring::*; +use garage_rpc::layout::*; use crate::data::*; use crate::replication::*; diff --git a/src/table/replication/fullcopy.rs b/src/table/replication/fullcopy.rs index 18682ace..30122f39 100644 --- a/src/table/replication/fullcopy.rs +++ b/src/table/replication/fullcopy.rs @@ -1,15 +1,22 @@ use std::sync::Arc; -use garage_rpc::ring::*; +use garage_rpc::layout::*; use garage_rpc::system::System; use garage_util::data::*; use crate::replication::*; +// TODO: find a way to track layout changes for this as well +// The hard thing is that this data is stored also on gateway nodes, +// whereas sharded data is stored only on non-Gateway nodes (storage nodes) +// Also we want to be more tolerant to failures of gateways so we don't +// want to do too much holding back of data when progress of gateway +// nodes is not reported in the layout history's ack/sync/sync_ack maps. + /// Full replication schema: all nodes store everything -/// Writes are disseminated in an epidemic manner in the network /// Advantage: do all reads locally, extremely fast /// Inconvenient: only suitable to reasonably small tables +/// Inconvenient: if some writes fail, nodes will read outdated data #[derive(Clone)] pub struct TableFullReplication { /// The membership manager of this node @@ -19,6 +26,13 @@ pub struct TableFullReplication { } impl TableReplication for TableFullReplication { + type WriteSets = Vec<Vec<Uuid>>; + + fn storage_nodes(&self, _hash: &Hash) -> Vec<Uuid> { + let layout = self.system.cluster_layout(); + layout.current().all_nodes().to_vec() + } + fn read_nodes(&self, _hash: &Hash) -> Vec<Uuid> { vec![self.system.id] } @@ -26,12 +40,11 @@ impl TableReplication for TableFullReplication { 1 } - fn write_nodes(&self, _hash: &Hash) -> Vec<Uuid> { - let ring = self.system.ring.borrow(); - ring.layout.node_ids().to_vec() + fn write_sets(&self, hash: &Hash) -> Self::WriteSets { + vec![self.storage_nodes(hash)] } fn write_quorum(&self) -> usize { - let nmembers = self.system.ring.borrow().layout.node_ids().len(); + let nmembers = self.system.cluster_layout().current().all_nodes().len(); if nmembers > self.max_faults { nmembers - self.max_faults } else { @@ -45,7 +58,18 @@ impl TableReplication for TableFullReplication { fn partition_of(&self, _hash: &Hash) -> Partition { 0u16 } - fn partitions(&self) -> Vec<(Partition, Hash)> { - vec![(0u16, [0u8; 32].into())] + + fn sync_partitions(&self) -> SyncPartitions { + let layout = self.system.cluster_layout(); + let layout_version = layout.current().version; + SyncPartitions { + layout_version, + partitions: vec![SyncPartition { + partition: 0u16, + first_hash: [0u8; 32].into(), + last_hash: [0xff; 32].into(), + storage_sets: vec![layout.current().all_nodes().to_vec()], + }], + } } } diff --git a/src/table/replication/parameters.rs b/src/table/replication/parameters.rs index f00815a2..78470f35 100644 --- a/src/table/replication/parameters.rs +++ b/src/table/replication/parameters.rs @@ -1,25 +1,44 @@ -use garage_rpc::ring::*; +use garage_rpc::layout::*; use garage_util::data::*; /// Trait to describe how a table shall be replicated pub trait TableReplication: Send + Sync + 'static { + type WriteSets: AsRef<Vec<Vec<Uuid>>> + AsMut<Vec<Vec<Uuid>>> + Send + Sync + 'static; + // See examples in table_sharded.rs and table_fullcopy.rs // To understand various replication methods + /// The entire list of all nodes that store a partition + fn storage_nodes(&self, hash: &Hash) -> Vec<Uuid>; + /// Which nodes to send read requests to fn read_nodes(&self, hash: &Hash) -> Vec<Uuid>; /// Responses needed to consider a read succesfull fn read_quorum(&self) -> usize; /// Which nodes to send writes to - fn write_nodes(&self, hash: &Hash) -> Vec<Uuid>; - /// Responses needed to consider a write succesfull + fn write_sets(&self, hash: &Hash) -> Self::WriteSets; + /// Responses needed to consider a write succesfull in each set fn write_quorum(&self) -> usize; fn max_write_errors(&self) -> usize; // Accessing partitions, for Merkle tree & sync /// Get partition for data with given hash fn partition_of(&self, hash: &Hash) -> Partition; - /// List of existing partitions - fn partitions(&self) -> Vec<(Partition, Hash)>; + /// List of partitions and nodes to sync with in current layout + fn sync_partitions(&self) -> SyncPartitions; +} + +#[derive(Debug)] +pub struct SyncPartitions { + pub layout_version: u64, + pub partitions: Vec<SyncPartition>, +} + +#[derive(Debug)] +pub struct SyncPartition { + pub partition: Partition, + pub first_hash: Hash, + pub last_hash: Hash, + pub storage_sets: Vec<Vec<Uuid>>, } diff --git a/src/table/replication/sharded.rs b/src/table/replication/sharded.rs index 1cf964af..8ba3700f 100644 --- a/src/table/replication/sharded.rs +++ b/src/table/replication/sharded.rs @@ -1,6 +1,6 @@ use std::sync::Arc; -use garage_rpc::ring::*; +use garage_rpc::layout::*; use garage_rpc::system::System; use garage_util::data::*; @@ -25,17 +25,21 @@ pub struct TableShardedReplication { } impl TableReplication for TableShardedReplication { + type WriteSets = WriteLock<Vec<Vec<Uuid>>>; + + fn storage_nodes(&self, hash: &Hash) -> Vec<Uuid> { + self.system.cluster_layout().storage_nodes_of(hash) + } + fn read_nodes(&self, hash: &Hash) -> Vec<Uuid> { - let ring = self.system.ring.borrow(); - ring.get_nodes(hash, self.replication_factor) + self.system.cluster_layout().read_nodes_of(hash) } fn read_quorum(&self) -> usize { self.read_quorum } - fn write_nodes(&self, hash: &Hash) -> Vec<Uuid> { - let ring = self.system.ring.borrow(); - ring.get_nodes(hash, self.replication_factor) + fn write_sets(&self, hash: &Hash) -> Self::WriteSets { + self.system.layout_manager.write_sets_of(hash) } fn write_quorum(&self) -> usize { self.write_quorum @@ -45,9 +49,38 @@ impl TableReplication for TableShardedReplication { } fn partition_of(&self, hash: &Hash) -> Partition { - self.system.ring.borrow().partition_of(hash) + self.system.cluster_layout().current().partition_of(hash) } - fn partitions(&self) -> Vec<(Partition, Hash)> { - self.system.ring.borrow().partitions() + + fn sync_partitions(&self) -> SyncPartitions { + let layout = self.system.cluster_layout(); + let layout_version = layout.ack_map_min(); + + let mut partitions = layout + .current() + .partitions() + .map(|(partition, first_hash)| { + let storage_sets = layout.storage_sets_of(&first_hash); + SyncPartition { + partition, + first_hash, + last_hash: [0u8; 32].into(), // filled in just after + storage_sets, + } + }) + .collect::<Vec<_>>(); + + for i in 0..partitions.len() { + partitions[i].last_hash = if i + 1 < partitions.len() { + partitions[i + 1].first_hash + } else { + [0xFFu8; 32].into() + }; + } + + SyncPartitions { + layout_version, + partitions, + } } } diff --git a/src/table/sync.rs b/src/table/sync.rs index 92a353c6..cd080df0 100644 --- a/src/table/sync.rs +++ b/src/table/sync.rs @@ -6,18 +6,19 @@ use arc_swap::ArcSwapOption; use async_trait::async_trait; use futures_util::stream::*; use opentelemetry::KeyValue; -use rand::Rng; +use rand::prelude::*; use serde::{Deserialize, Serialize}; use serde_bytes::ByteBuf; use tokio::select; -use tokio::sync::{mpsc, watch}; +use tokio::sync::{mpsc, watch, Notify}; use garage_util::background::*; use garage_util::data::*; use garage_util::encode::{debug_serialize, nonversioned_encode}; use garage_util::error::{Error, OkOrMessage}; -use garage_rpc::ring::*; +use garage_rpc::layout::*; +use garage_rpc::rpc_helper::QuorumSetResultTracker; use garage_rpc::system::System; use garage_rpc::*; @@ -52,16 +53,6 @@ impl Rpc for SyncRpc { type Response = Result<SyncRpc, Error>; } -#[derive(Debug, Clone)] -struct TodoPartition { - partition: Partition, - begin: Hash, - end: Hash, - - // Are we a node that stores this partition or not? - retain: bool, -} - impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { pub(crate) fn new( system: Arc<System>, @@ -91,10 +82,10 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { bg.spawn_worker(SyncWorker { syncer: self.clone(), - ring_recv: self.system.ring.clone(), - ring: self.system.ring.borrow().clone(), + layout_notify: self.system.layout_notify(), + layout_digest: self.system.cluster_layout().sync_digest(), add_full_sync_rx, - todo: vec![], + todo: None, next_full_sync: Instant::now() + Duration::from_secs(20), }); } @@ -112,53 +103,56 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { async fn sync_partition( self: &Arc<Self>, - partition: &TodoPartition, + partition: &SyncPartition, must_exit: &mut watch::Receiver<bool>, ) -> Result<(), Error> { - if partition.retain { - let my_id = self.system.id; - - let nodes = self - .data - .replication - .write_nodes(&partition.begin) - .into_iter() - .filter(|node| *node != my_id) - .collect::<Vec<_>>(); + let my_id = self.system.id; + let retain = partition.storage_sets.iter().any(|x| x.contains(&my_id)); + if retain { debug!( "({}) Syncing {:?} with {:?}...", F::TABLE_NAME, partition, - nodes + partition.storage_sets ); - let mut sync_futures = nodes - .iter() + let mut result_tracker = QuorumSetResultTracker::new( + &partition.storage_sets, + self.data.replication.write_quorum(), + ); + + let mut sync_futures = result_tracker + .nodes + .keys() + .copied() .map(|node| { - self.clone() - .do_sync_with(partition.clone(), *node, must_exit.clone()) + let must_exit = must_exit.clone(); + async move { + if node == my_id { + (node, Ok(())) + } else { + (node, self.do_sync_with(partition, node, must_exit).await) + } + } }) .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: {}", F::TABLE_NAME, e); + while let Some((node, res)) = sync_futures.next().await { + if let Err(e) = &res { + warn!("({}) Sync error with {:?}: {}", F::TABLE_NAME, node, e); } + result_tracker.register_result(node, res); } - if n_errors > self.data.replication.max_write_errors() { - return Err(Error::Message(format!( - "Sync failed with too many nodes (should have been: {:?}).", - nodes - ))); + + if result_tracker.too_many_failures() { + Err(result_tracker.quorum_error()) + } else { + Ok(()) } } else { - self.offload_partition(&partition.begin, &partition.end, must_exit) - .await?; + self.offload_partition(&partition.first_hash, &partition.last_hash, must_exit) + .await } - - Ok(()) } // Offload partition: this partition is not something we are storing, @@ -188,12 +182,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { } if !items.is_empty() { - let nodes = self - .data - .replication - .write_nodes(begin) - .into_iter() - .collect::<Vec<_>>(); + let nodes = self.data.replication.storage_nodes(begin); if nodes.contains(&self.system.id) { warn!( "({}) Interrupting offload as partitions seem to have changed", @@ -217,7 +206,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { end, counter ); - self.offload_items(&items, &nodes[..]).await?; + self.offload_items(&items, &nodes).await?; } else { break; } @@ -244,7 +233,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { } self.system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, nodes, @@ -284,8 +273,8 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { } async fn do_sync_with( - self: Arc<Self>, - partition: TodoPartition, + self: &Arc<Self>, + partition: &SyncPartition, who: Uuid, must_exit: watch::Receiver<bool>, ) -> Result<(), Error> { @@ -305,7 +294,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { // If so, do nothing. let root_resp = self .system - .rpc + .rpc_helper() .call( &self.endpoint, who, @@ -361,7 +350,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { // and compare it with local node let remote_node = match self .system - .rpc + .rpc_helper() .call( &self.endpoint, who, @@ -437,7 +426,7 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> { let rpc_resp = self .system - .rpc + .rpc_helper() .call( &self.endpoint, who, @@ -492,75 +481,41 @@ impl<F: TableSchema, R: TableReplication> EndpointHandler<SyncRpc> for TableSync struct SyncWorker<F: TableSchema, R: TableReplication> { syncer: Arc<TableSyncer<F, R>>, - ring_recv: watch::Receiver<Arc<Ring>>, - ring: Arc<Ring>, + + layout_notify: Arc<Notify>, + layout_digest: SyncLayoutDigest, + add_full_sync_rx: mpsc::UnboundedReceiver<()>, - todo: Vec<TodoPartition>, next_full_sync: Instant, + + todo: Option<SyncPartitions>, } impl<F: TableSchema, R: TableReplication> SyncWorker<F, R> { - fn add_full_sync(&mut self) { - let system = &self.syncer.system; - let data = &self.syncer.data; - - let my_id = system.id; - - self.todo.clear(); - - let partitions = data.replication.partitions(); - - for i in 0..partitions.len() { - let begin = partitions[i].1; - - let end = if i + 1 < partitions.len() { - partitions[i + 1].1 - } else { - [0xFFu8; 32].into() - }; - - let nodes = data.replication.write_nodes(&begin); - - let retain = nodes.contains(&my_id); - if !retain { - // Check if we have some data to send, otherwise skip - match data.store.range(begin..end) { - Ok(mut iter) => { - if iter.next().is_none() { - continue; - } - } - Err(e) => { - warn!("DB error in add_full_sync: {}", e); - continue; - } - } - } - - self.todo.push(TodoPartition { - partition: partitions[i].0, - begin, - end, - retain, - }); + fn check_add_full_sync(&mut self) { + let layout_digest = self.syncer.system.cluster_layout().sync_digest(); + if layout_digest != self.layout_digest { + self.layout_digest = layout_digest; + info!( + "({}) Layout versions changed ({:?}), adding full sync to syncer todo list", + F::TABLE_NAME, + layout_digest, + ); + self.add_full_sync(); } - - self.next_full_sync = Instant::now() + ANTI_ENTROPY_INTERVAL; } - fn pop_task(&mut self) -> Option<TodoPartition> { - if self.todo.is_empty() { - return None; - } + fn add_full_sync(&mut self) { + let mut partitions = self.syncer.data.replication.sync_partitions(); + info!( + "{}: Adding full sync for ack layout version {}", + F::TABLE_NAME, + partitions.layout_version + ); - let i = rand::thread_rng().gen_range(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) - } + partitions.partitions.shuffle(&mut thread_rng()); + self.todo = Some(partitions); + self.next_full_sync = Instant::now() + ANTI_ENTROPY_INTERVAL; } } @@ -572,14 +527,48 @@ impl<F: TableSchema, R: TableReplication> Worker for SyncWorker<F, R> { fn status(&self) -> WorkerStatus { WorkerStatus { - queue_length: Some(self.todo.len() as u64), + queue_length: Some(self.todo.as_ref().map(|x| x.partitions.len()).unwrap_or(0) as u64), ..Default::default() } } async fn work(&mut self, must_exit: &mut watch::Receiver<bool>) -> Result<WorkerState, Error> { - if let Some(partition) = self.pop_task() { - self.syncer.sync_partition(&partition, must_exit).await?; + self.check_add_full_sync(); + + if let Some(todo) = &mut self.todo { + let partition = todo.partitions.pop().unwrap(); + + // process partition + if let Err(e) = self.syncer.sync_partition(&partition, must_exit).await { + error!( + "{}: Failed to sync partition {:?}: {}", + F::TABLE_NAME, + partition, + e + ); + // if error, put partition back at the other side of the queue, + // so that other partitions will be tried in the meantime + todo.partitions.insert(0, partition); + // TODO: returning an error here will cause the background job worker + // to delay this task for some time, but maybe we don't want to + // delay it if there are lots of failures from nodes that are gone + // (we also don't want zero delays as that will cause lots of useless retries) + return Err(e); + } + + if todo.partitions.is_empty() { + info!( + "{}: Completed full sync for ack layout version {}", + F::TABLE_NAME, + todo.layout_version + ); + self.syncer + .system + .layout_manager + .sync_table_until(F::TABLE_NAME, todo.layout_version); + self.todo = None; + } + Ok(WorkerState::Busy) } else { Ok(WorkerState::Idle) @@ -593,22 +582,16 @@ impl<F: TableSchema, R: TableReplication> Worker for SyncWorker<F, R> { self.add_full_sync(); } }, - _ = self.ring_recv.changed() => { - let new_ring = self.ring_recv.borrow(); - if !Arc::ptr_eq(&new_ring, &self.ring) { - self.ring = new_ring.clone(); - drop(new_ring); - debug!("({}) Ring changed, adding full sync to syncer todo list", F::TABLE_NAME); - self.add_full_sync(); - } + _ = self.layout_notify.notified() => { + self.check_add_full_sync(); }, _ = tokio::time::sleep_until(self.next_full_sync.into()) => { self.add_full_sync(); } } - match self.todo.is_empty() { - false => WorkerState::Busy, - true => WorkerState::Idle, + match self.todo.is_some() { + true => WorkerState::Busy, + false => WorkerState::Idle, } } } diff --git a/src/table/table.rs b/src/table/table.rs index 7ad79677..a5be2910 100644 --- a/src/table/table.rs +++ b/src/table/table.rs @@ -20,6 +20,7 @@ use garage_util::error::Error; use garage_util::metrics::RecordDuration; use garage_util::migrate::Migrate; +use garage_rpc::rpc_helper::QuorumSetResultTracker; use garage_rpc::system::System; use garage_rpc::*; @@ -80,6 +81,8 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { let syncer = TableSyncer::new(system.clone(), data.clone(), merkle_updater.clone()); let gc = TableGc::new(system.clone(), data.clone()); + system.layout_manager.add_table(F::TABLE_NAME); + let table = Arc::new(Self { system, data, @@ -117,16 +120,16 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { async fn insert_internal(&self, e: &F::E) -> Result<(), Error> { let hash = e.partition_key().hash(); - let who = self.data.replication.write_nodes(&hash); + let who = self.data.replication.write_sets(&hash); let e_enc = Arc::new(ByteBuf::from(e.encode()?)); let rpc = TableRpc::<F>::Update(vec![e_enc]); self.system - .rpc - .try_call_many( + .rpc_helper() + .try_write_many_sets( &self.endpoint, - &who[..], + who.as_ref(), rpc, RequestStrategy::with_priority(PRIO_NORMAL) .with_quorum(self.data.replication.write_quorum()), @@ -141,7 +144,7 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { self.data.queue_insert(tx, e) } - pub async fn insert_many<I, IE>(&self, entries: I) -> Result<(), Error> + pub async fn insert_many<I, IE>(self: &Arc<Self>, entries: I) -> Result<(), Error> where I: IntoIterator<Item = IE> + Send + Sync, IE: Borrow<F::E> + Send + Sync, @@ -159,51 +162,123 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { Ok(()) } - async fn insert_many_internal<I, IE>(&self, entries: I) -> Result<(), Error> + async fn insert_many_internal<I, IE>(self: &Arc<Self>, entries: I) -> Result<(), Error> where I: IntoIterator<Item = IE> + Send + Sync, IE: Borrow<F::E> + Send + Sync, { - let mut call_list: HashMap<_, Vec<_>> = HashMap::new(); - + // The different items will have to be stored on possibly different nodes. + // We will here batch all items into a single request for each concerned + // node, with all of the entries it must store within that request. + // Each entry has to be saved to a specific list of "write sets", i.e. a set + // of node within wich a quorum must be achieved. In normal operation, there + // is a single write set which corresponds to the quorum in the current + // cluster layout, but when the layout is updated, multiple write sets might + // have to be handled at once. Here, since we are sending many entries, we + // will have to handle many write sets in all cases. The algorihtm is thus + // to send one request to each node with all the items it must save, + // and keep track of the OK responses within each write set: if for all sets + // a quorum of nodes has answered OK, then the insert has succeeded and + // consistency properties (read-after-write) are preserved. + + let quorum = self.data.replication.write_quorum(); + + // Serialize all entries and compute the write sets for each of them. + // In the case of sharded table replication, this also takes an "ack lock" + // to the layout manager to avoid ack'ing newer versions which are not + // taken into account by writes in progress (the ack can happen later, once + // all writes that didn't take the new layout into account are finished). + // These locks are released when entries_vec is dropped, i.e. when this + // function returns. + let mut entries_vec = Vec::new(); for entry in entries.into_iter() { let entry = entry.borrow(); let hash = entry.partition_key().hash(); - let who = self.data.replication.write_nodes(&hash); + let mut write_sets = self.data.replication.write_sets(&hash); + for set in write_sets.as_mut().iter_mut() { + // Sort nodes in each write sets to merge write sets with same + // nodes but in possibly different orders + set.sort(); + } let e_enc = Arc::new(ByteBuf::from(entry.encode()?)); - for node in who { - call_list.entry(node).or_default().push(e_enc.clone()); + entries_vec.push((write_sets, e_enc)); + } + + // Compute a deduplicated list of all of the write sets, + // and compute an index from each node to the position of the sets in which + // it takes part, to optimize the detection of a quorum. + let mut write_sets = entries_vec + .iter() + .flat_map(|(wss, _)| wss.as_ref().iter().map(|ws| ws.as_slice())) + .collect::<Vec<&[Uuid]>>(); + write_sets.sort(); + write_sets.dedup(); + + let mut result_tracker = QuorumSetResultTracker::new(&write_sets, quorum); + + // Build a map of all nodes to the entries that must be sent to that node. + let mut call_list: HashMap<Uuid, Vec<_>> = HashMap::new(); + for (write_sets, entry_enc) in entries_vec.iter() { + for write_set in write_sets.as_ref().iter() { + for node in write_set.iter() { + let node_entries = call_list.entry(*node).or_default(); + match node_entries.last() { + Some(x) if Arc::ptr_eq(x, entry_enc) => { + // skip if entry already in list to send to this node + // (could happen if node is in several write sets for this entry) + } + _ => { + node_entries.push(entry_enc.clone()); + } + } + } } } - let call_futures = call_list.drain().map(|(node, entries)| async move { - let rpc = TableRpc::<F>::Update(entries); - - let resp = self - .system - .rpc - .call( - &self.endpoint, - node, - rpc, - RequestStrategy::with_priority(PRIO_NORMAL), - ) - .await?; - Ok::<_, Error>((node, resp)) + // Build futures to actually perform each of the corresponding RPC calls + let call_futures = call_list.into_iter().map(|(node, entries)| { + let this = self.clone(); + async move { + let rpc = TableRpc::<F>::Update(entries); + let resp = this + .system + .rpc_helper() + .call( + &this.endpoint, + node, + rpc, + RequestStrategy::with_priority(PRIO_NORMAL).with_quorum(quorum), + ) + .await; + (node, resp) + } }); + + // Run all requests in parallel thanks to FuturesUnordered, and collect results. let mut resps = call_futures.collect::<FuturesUnordered<_>>(); - let mut errors = vec![]; - while let Some(resp) = resps.next().await { - if let Err(e) = resp { - errors.push(e); + while let Some((node, resp)) = resps.next().await { + result_tracker.register_result(node, resp.map(|_| ())); + + if result_tracker.all_quorums_ok() { + // Success + + // Continue all other requests in background + tokio::spawn(async move { + resps.collect::<Vec<(Uuid, Result<_, _>)>>().await; + }); + + return Ok(()); + } + + if result_tracker.too_many_failures() { + // Too many errors in this set, we know we won't get a quorum + break; } } - if errors.len() > self.data.replication.max_write_errors() { - Err(Error::Message("Too many errors".into())) - } else { - Ok(()) - } + + // Failure, could not get quorum within at least one set + Err(result_tracker.quorum_error()) } pub async fn get( @@ -236,14 +311,13 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { let rpc = TableRpc::<F>::ReadEntry(partition_key.clone(), sort_key.clone()); let resps = self .system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, - &who[..], + &who, rpc, RequestStrategy::with_priority(PRIO_NORMAL) - .with_quorum(self.data.replication.read_quorum()) - .interrupt_after_quorum(true), + .with_quorum(self.data.replication.read_quorum()), ) .await?; @@ -332,14 +406,13 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { let resps = self .system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, - &who[..], + &who, rpc, RequestStrategy::with_priority(PRIO_NORMAL) - .with_quorum(self.data.replication.read_quorum()) - .interrupt_after_quorum(true), + .with_quorum(self.data.replication.read_quorum()), ) .await?; @@ -411,7 +484,7 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> { async fn repair_on_read(&self, who: &[Uuid], what: F::E) -> Result<(), Error> { let what_enc = Arc::new(ByteBuf::from(what.encode()?)); self.system - .rpc + .rpc_helper() .try_call_many( &self.endpoint, who, |