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Merge #3331

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3331: Limit the number of concurrently opened indexes r=dureuill a=dureuill

# Pull Request

## Related issue
Relevant to #1841, fixes #3382

## What does this PR do?

### User standpoint

- Limit the number of concurrently opened indexes (currently, the number of indexes that can be concurrently opened is computed at startup)
- When too many an index is opened, the least recently used one is closed and its virtual memory released.
- This allows a user to have an arbitrary number of indexes of an arbitrary size

### Implementation standpoint

- Added a LRU cache map in `index-scheduler::lru`. A more complete implementation  (eg with helper functions not used here) is available but would better fit a dedicated crate.
- Use the LRU cache map in the `IndexScheduler`. To simplify the lifecycle of indexes, they are never removed from the cache when they are in the middle of a resize or delete operation. To achieve this, an intermediate `Vec` stores the UUIDs of the indexes that are in the middle of such an operation.
- Upon creating the index scheduler object, compute the total virtual memory that is adressable by using a dichotomic search on the max size of an index. Use this as a base to compute the number of indexes that can be open with 2TiB per index. If the virtual memory address space is lower than 2TiB, then only allow for 1 index of a fraction of that size.

Co-authored-by: Louis Dureuil <louis@meilisearch.com>
This commit is contained in:
bors[bot] 2023-02-23 14:20:52 +00:00 committed by GitHub
commit ca25904c26
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14 changed files with 977 additions and 189 deletions
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11
index-scheduler/src/batch.rs
View File

@ -788,15 +788,15 @@ impl IndexScheduler {
dump_tasks.flush()?;
// 3. Dump the indexes
for (uid, index) in self.index_mapper.indexes(&rtxn)? {
self.index_mapper.try_for_each_index(&rtxn, |uid, index| -> Result<()> {
let rtxn = index.read_txn()?;
let metadata = IndexMetadata {
uid: uid.clone(),
uid: uid.to_owned(),
primary_key: index.primary_key(&rtxn)?.map(String::from),
created_at: index.created_at(&rtxn)?,
updated_at: index.updated_at(&rtxn)?,
};
let mut index_dumper = dump.create_index(&uid, &metadata)?;
let mut index_dumper = dump.create_index(uid, &metadata)?;
let fields_ids_map = index.fields_ids_map(&rtxn)?;
let all_fields: Vec<_> = fields_ids_map.iter().map(|(id, _)| id).collect();
@ -809,9 +809,10 @@ impl IndexScheduler {
}
// 3.2. Dump the settings
let settings = meilisearch_types::settings::settings(&index, &rtxn)?;
let settings = meilisearch_types::settings::settings(index, &rtxn)?;
index_dumper.settings(&settings)?;
}
Ok(())
})?;
let dump_uid = started_at.format(format_description!(
"[year repr:full][month repr:numerical][day padding:zero]-[hour padding:zero][minute padding:zero][second padding:zero][subsecond digits:3]"

370
index-scheduler/src/index_mapper/index_map.rs Normal file
View File

@ -0,0 +1,370 @@
/// the map size to use when we don't succeed in reading it in indexes.
const DEFAULT_MAP_SIZE: usize = 10 * 1024 * 1024 * 1024; // 10 GiB
use std::collections::BTreeMap;
use std::path::Path;
use std::time::Duration;
use meilisearch_types::heed::{EnvClosingEvent, EnvOpenOptions};
use meilisearch_types::milli::Index;
use time::OffsetDateTime;
use uuid::Uuid;
use super::IndexStatus::{self, Available, BeingDeleted, Closing, Missing};
use crate::lru::{InsertionOutcome, LruMap};
use crate::{clamp_to_page_size, Result};
/// Keep an internally consistent view of the open indexes in memory.
///
/// This view is made of an LRU cache that will evict the least frequently used indexes when new indexes are opened.
/// Indexes that are being closed (for resizing or due to cache eviction) or deleted cannot be evicted from the cache and
/// are stored separately.
///
/// This view provides operations to change the state of the index as it is known in memory:
/// open an index (making it available for queries), close an index (specifying the new size it should be opened with),
/// delete an index.
///
/// External consistency with the other bits of data of an index is provided by the `IndexMapper` parent structure.
pub struct IndexMap {
/// A LRU map of indexes that are in the open state and available for queries.
available: LruMap<Uuid, Index>,
/// A map of indexes that are not available for queries, either because they are being deleted
/// or because they are being closed.
///
/// If they are being deleted, the UUID points to `None`.
unavailable: BTreeMap<Uuid, Option<ClosingIndex>>,
/// A monotonically increasing generation number, used to differentiate between multiple successive index closing requests.
///
/// Because multiple readers could be waiting on an index to close, the following could theoretically happen:
///
/// 1. Multiple readers wait for the index closing to occur.
/// 2. One of them "wins the race", takes the lock and then removes the index that finished closing from the map.
/// 3. The index is reopened, but must be closed again (such as being resized again).
/// 4. One reader that "lost the race" in (2) wakes up and tries to take the lock and remove the index from the map.
///
/// In that situation, the index may or may not have finished closing. The `generation` field allows to remember which
/// closing request was made, so the reader that "lost the race" has the old generation and will need to wait again for the index
/// to close.
generation: usize,
}
#[derive(Clone)]
pub struct ClosingIndex {
uuid: Uuid,
closing_event: EnvClosingEvent,
map_size: usize,
generation: usize,
}
impl ClosingIndex {
/// Waits for the index to be definitely closed.
///
/// To avoid blocking, users should relinquish their locks to the IndexMap before calling this function.
///
/// After the index is physically closed, the in memory map must still be updated to take this into account.
/// To do so, a `ReopenableIndex` is returned, that can be used to either definitely close or definitely open
/// the index without waiting anymore.
pub fn wait_timeout(self, timeout: Duration) -> Option<ReopenableIndex> {
self.closing_event.wait_timeout(timeout).then_some(ReopenableIndex {
uuid: self.uuid,
map_size: self.map_size,
generation: self.generation,
})
}
}
pub struct ReopenableIndex {
uuid: Uuid,
map_size: usize,
generation: usize,
}
impl ReopenableIndex {
/// Attempts to reopen the index, which can result in the index being reopened again or not
/// (e.g. if another thread already opened and closed the index again).
///
/// Use get again on the IndexMap to get the updated status.
///
/// Fails if the underlying index creation fails.
///
/// # Status table
///
/// | Previous Status | New Status |
/// |-----------------|----------------------------------------------|
/// | Missing | Missing |
/// | BeingDeleted | BeingDeleted |
/// | Closing | Available or Closing depending on generation |
/// | Available | Available |
///
pub fn reopen(self, map: &mut IndexMap, path: &Path) -> Result<()> {
if let Closing(reopen) = map.get(&self.uuid) {
if reopen.generation != self.generation {
return Ok(());
}
map.unavailable.remove(&self.uuid);
map.create(&self.uuid, path, None, self.map_size)?;
}
Ok(())
}
/// Attempts to close the index, which may or may not result in the index being closed
/// (e.g. if another thread already reopened the index again).
///
/// Use get again on the IndexMap to get the updated status.
///
/// # Status table
///
/// | Previous Status | New Status |
/// |-----------------|--------------------------------------------|
/// | Missing | Missing |
/// | BeingDeleted | BeingDeleted |
/// | Closing | Missing or Closing depending on generation |
/// | Available | Available |
pub fn close(self, map: &mut IndexMap) {
if let Closing(reopen) = map.get(&self.uuid) {
if reopen.generation != self.generation {
return;
}
map.unavailable.remove(&self.uuid);
}
}
}
impl IndexMap {
pub fn new(cap: usize) -> IndexMap {
Self { unavailable: Default::default(), available: LruMap::new(cap), generation: 0 }
}
/// Gets the current status of an index in the map.
///
/// If the index is available it can be accessed from the returned status.
pub fn get(&self, uuid: &Uuid) -> IndexStatus {
self.available
.get(uuid)
.map(|index| Available(index.clone()))
.unwrap_or_else(|| self.get_unavailable(uuid))
}
fn get_unavailable(&self, uuid: &Uuid) -> IndexStatus {
match self.unavailable.get(uuid) {
Some(Some(reopen)) => Closing(reopen.clone()),
Some(None) => BeingDeleted,
None => Missing,
}
}
/// Attempts to create a new index that wasn't existing before.
///
/// # Status table
///
/// | Previous Status | New Status |
/// |-----------------|------------|
/// | Missing | Available |
/// | BeingDeleted | panics |
/// | Closing | panics |
/// | Available | panics |
///
pub fn create(
&mut self,
uuid: &Uuid,
path: &Path,
date: Option<(OffsetDateTime, OffsetDateTime)>,
map_size: usize,
) -> Result<Index> {
if !matches!(self.get_unavailable(uuid), Missing) {
panic!("Attempt to open an index that was unavailable");
}
let index = create_or_open_index(path, date, map_size)?;
match self.available.insert(*uuid, index.clone()) {
InsertionOutcome::InsertedNew => (),
InsertionOutcome::Evicted(evicted_uuid, evicted_index) => {
self.close(evicted_uuid, evicted_index, 0);
}
InsertionOutcome::Replaced(_) => {
panic!("Attempt to open an index that was already opened")
}
}
Ok(index)
}
/// Increases the current generation. See documentation for this field.
///
/// In the unlikely event that the 2^64 generations would have been exhausted, we simply wrap-around.
///
/// For this to cause an issue, one should be able to stop a reader in time after it got a `ReopenableIndex` and before it takes the lock
/// to remove it from the unavailable map, and keep the reader in this frozen state for 2^64 closing of other indexes.
///
/// This seems overwhelmingly impossible to achieve in practice.
fn next_generation(&mut self) -> usize {
self.generation = self.generation.wrapping_add(1);
self.generation
}
/// Attempts to close an index.
///
/// # Status table
///
/// | Previous Status | New Status |
/// |-----------------|---------------|
/// | Missing | Missing |
/// | BeingDeleted | BeingDeleted |
/// | Closing | Closing |
/// | Available | Closing |
///
pub fn close_for_resize(&mut self, uuid: &Uuid, map_size_growth: usize) {
let Some(index) = self.available.remove(uuid) else { return; };
self.close(*uuid, index, map_size_growth);
}
fn close(&mut self, uuid: Uuid, index: Index, map_size_growth: usize) {
let map_size = index.map_size().unwrap_or(DEFAULT_MAP_SIZE) + map_size_growth;
let closing_event = index.prepare_for_closing();
let generation = self.next_generation();
self.unavailable
.insert(uuid, Some(ClosingIndex { uuid, closing_event, map_size, generation }));
}
/// Attempts to delete and index.
///
/// `end_deletion` must be called just after.
///
/// # Status table
///
/// | Previous Status | New Status | Return value |
/// |-----------------|--------------|-----------------------------|
/// | Missing | BeingDeleted | Ok(None) |
/// | BeingDeleted | BeingDeleted | Err(None) |
/// | Closing | Closing | Err(Some(reopen)) |
/// | Available | BeingDeleted | Ok(Some(env_closing_event)) |
pub fn start_deletion(
&mut self,
uuid: &Uuid,
) -> std::result::Result<Option<EnvClosingEvent>, Option<ClosingIndex>> {
if let Some(index) = self.available.remove(uuid) {
self.unavailable.insert(*uuid, None);
return Ok(Some(index.prepare_for_closing()));
}
match self.unavailable.remove(uuid) {
Some(Some(reopen)) => Err(Some(reopen)),
Some(None) => Err(None),
None => Ok(None),
}
}
/// Marks that an index deletion finished.
///
/// Must be used after calling `start_deletion`.
///
/// # Status table
///
/// | Previous Status | New Status |
/// |-----------------|------------|
/// | Missing | Missing |
/// | BeingDeleted | Missing |
/// | Closing | panics |
/// | Available | panics |
pub fn end_deletion(&mut self, uuid: &Uuid) {
assert!(
self.available.get(uuid).is_none(),
"Attempt to finish deletion of an index that was not being deleted"
);
// Do not panic if the index was Missing or BeingDeleted
assert!(
!matches!(self.unavailable.remove(uuid), Some(Some(_))),
"Attempt to finish deletion of an index that was being closed"
);
}
}
/// Create or open an index in the specified path.
/// The path *must* exist or an error will be thrown.
fn create_or_open_index(
path: &Path,
date: Option<(OffsetDateTime, OffsetDateTime)>,
map_size: usize,
) -> Result<Index> {
let mut options = EnvOpenOptions::new();
options.map_size(clamp_to_page_size(map_size));
options.max_readers(1024);
if let Some((created, updated)) = date {
Ok(Index::new_with_creation_dates(options, path, created, updated)?)
} else {
Ok(Index::new(options, path)?)
}
}
/// Putting the tests of the LRU down there so we have access to the cache's private members
#[cfg(test)]
mod tests {
use meilisearch_types::heed::Env;
use meilisearch_types::Index;
use uuid::Uuid;
use super::super::IndexMapper;
use crate::tests::IndexSchedulerHandle;
use crate::utils::clamp_to_page_size;
use crate::IndexScheduler;
impl IndexMapper {
fn test() -> (Self, Env, IndexSchedulerHandle) {
let (index_scheduler, handle) = IndexScheduler::test(true, vec![]);
(index_scheduler.index_mapper, index_scheduler.env, handle)
}
}
fn check_first_unavailable(mapper: &IndexMapper, expected_uuid: Uuid, is_closing: bool) {
let index_map = mapper.index_map.read().unwrap();
let (uuid, state) = index_map.unavailable.first_key_value().unwrap();
assert_eq!(uuid, &expected_uuid);
assert_eq!(state.is_some(), is_closing);
}
#[test]
fn evict_indexes() {
let (mapper, env, _handle) = IndexMapper::test();
let mut uuids = vec![];
// LRU cap + 1
for i in 0..(5 + 1) {
let index_name = format!("index-{i}");
let wtxn = env.write_txn().unwrap();
mapper.create_index(wtxn, &index_name, None).unwrap();
let txn = env.read_txn().unwrap();
uuids.push(mapper.index_mapping.get(&txn, &index_name).unwrap().unwrap());
}
// index-0 was evicted
check_first_unavailable(&mapper, uuids[0], true);
// get back the evicted index
let wtxn = env.write_txn().unwrap();
mapper.create_index(wtxn, "index-0", None).unwrap();
// Least recently used is now index-1
check_first_unavailable(&mapper, uuids[1], true);
}
#[test]
fn resize_index() {
let (mapper, env, _handle) = IndexMapper::test();
let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
assert_index_size(index, mapper.index_base_map_size);
mapper.resize_index(&env.read_txn().unwrap(), "index").unwrap();
let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
assert_index_size(index, mapper.index_base_map_size + mapper.index_growth_amount);
mapper.resize_index(&env.read_txn().unwrap(), "index").unwrap();
let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
assert_index_size(index, mapper.index_base_map_size + mapper.index_growth_amount * 2);
}
fn assert_index_size(index: Index, expected: usize) {
let expected = clamp_to_page_size(expected);
let index_map_size = index.map_size().unwrap();
assert_eq!(index_map_size, expected);
}
}

314
index-scheduler/src/index_mapper.rs → index-scheduler/src/index_mapper/mod.rs
View File

@ -1,21 +1,22 @@
use std::collections::hash_map::Entry;
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use std::path::PathBuf;
use std::sync::{Arc, RwLock};
use std::time::Duration;
use std::{fs, thread};
use log::error;
use meilisearch_types::heed::types::Str;
use meilisearch_types::heed::{Database, Env, EnvOpenOptions, RoTxn, RwTxn};
use meilisearch_types::heed::{Database, Env, RoTxn, RwTxn};
use meilisearch_types::milli::update::IndexerConfig;
use meilisearch_types::milli::Index;
use synchronoise::SignalEvent;
use time::OffsetDateTime;
use uuid::Uuid;
use self::IndexStatus::{Available, BeingDeleted, BeingResized};
use self::index_map::IndexMap;
use self::IndexStatus::{Available, BeingDeleted, Closing, Missing};
use crate::uuid_codec::UuidCodec;
use crate::{clamp_to_page_size, Error, Result};
use crate::{Error, Result};
mod index_map;
const INDEX_MAPPING: &str = "index-mapping";
@ -26,17 +27,38 @@ const INDEX_MAPPING: &str = "index-mapping";
/// 2. Opening indexes and storing references to these opened indexes
/// 3. Accessing indexes through their uuid
/// 4. Mapping a user-defined name to each index uuid.
///
/// # Implementation notes
///
/// An index exists as 3 bits of data:
/// 1. The index data on disk, that can exist in 3 states: Missing, Present, or BeingDeleted.
/// 2. The persistent database containing the association between the index' name and its UUID,
/// that can exist in 2 states: Missing or Present.
/// 3. The state of the index in the in-memory `IndexMap`, that can exist in multiple states:
/// - Missing
/// - Available
/// - Closing (because an index needs resizing or was evicted from the cache)
/// - BeingDeleted
///
/// All of this data should be kept consistent between index operations, which is achieved by the `IndexMapper`
/// with the use of the following primitives:
/// - A RwLock on the `IndexMap`.
/// - Transactions on the association database.
/// - ClosingEvent signals emitted when closing an environment.
#[derive(Clone)]
pub struct IndexMapper {
/// Keep track of the opened indexes. Used mainly by the index resolver.
index_map: Arc<RwLock<HashMap<Uuid, IndexStatus>>>,
index_map: Arc<RwLock<IndexMap>>,
/// Map an index name with an index uuid currently available on disk.
pub(crate) index_mapping: Database<Str, UuidCodec>,
/// Path to the folder where the LMDB environments of each index are.
base_path: PathBuf,
index_size: usize,
/// The map size an index is opened with on the first time.
index_base_map_size: usize,
/// The quantity by which the map size of an index is incremented upon reopening, in bytes.
index_growth_amount: usize,
pub indexer_config: Arc<IndexerConfig>,
}
@ -44,10 +66,12 @@ pub struct IndexMapper {
#[allow(clippy::large_enum_variant)]
#[derive(Clone)]
pub enum IndexStatus {
/// Not currently in the index map.
Missing,
/// Do not insert it back in the index map as it is currently being deleted.
BeingDeleted,
/// Temporarily do not insert the index in the index map as it is currently being resized.
BeingResized(Arc<SignalEvent>),
/// Temporarily do not insert the index in the index map as it is currently being resized/evicted from the map.
Closing(index_map::ClosingIndex),
/// You can use the index without worrying about anything.
Available(Index),
}
@ -56,37 +80,21 @@ impl IndexMapper {
pub fn new(
env: &Env,
base_path: PathBuf,
index_size: usize,
index_base_map_size: usize,
index_growth_amount: usize,
index_count: usize,
indexer_config: IndexerConfig,
) -> Result<Self> {
Ok(Self {
index_map: Arc::default(),
index_map: Arc::new(RwLock::new(IndexMap::new(index_count))),
index_mapping: env.create_database(Some(INDEX_MAPPING))?,
base_path,
index_size,
index_base_map_size,
index_growth_amount,
indexer_config: Arc::new(indexer_config),
})
}
/// Create or open an index in the specified path.
/// The path *must* exists or an error will be thrown.
fn create_or_open_index(
&self,
path: &Path,
date: Option<(OffsetDateTime, OffsetDateTime)>,
map_size: usize,
) -> Result<Index> {
let mut options = EnvOpenOptions::new();
options.map_size(clamp_to_page_size(map_size));
options.max_readers(1024);
if let Some((created, updated)) = date {
Ok(Index::new_with_creation_dates(options, path, created, updated)?)
} else {
Ok(Index::new(options, path)?)
}
}
/// Get or create the index.
pub fn create_index(
&self,
@ -106,16 +114,17 @@ impl IndexMapper {
let index_path = self.base_path.join(uuid.to_string());
fs::create_dir_all(&index_path)?;
let index = self.create_or_open_index(&index_path, date, self.index_size)?;
wtxn.commit()?;
// Error if the UUIDv4 somehow already exists in the map, since it should be fresh.
// This is very unlikely to happen in practice.
// TODO: it would be better to lazily create the index. But we need an Index::open function for milli.
if self.index_map.write().unwrap().insert(uuid, Available(index.clone())).is_some()
{
panic!("Uuid v4 conflict: index with UUID {uuid} already exists.");
}
let index = self.index_map.write().unwrap().create(
&uuid,
&index_path,
date,
self.index_base_map_size,
)?;
wtxn.commit()?;
Ok(index)
}
@ -135,23 +144,42 @@ impl IndexMapper {
assert!(self.index_mapping.delete(&mut wtxn, name)?);
wtxn.commit()?;
// We remove the index from the in-memory index map.
let mut tries = 0;
// Attempts to remove the index from the in-memory index map in a loop.
//
// If the index is currently being closed, we will wait for it to be closed and retry getting it in a subsequent
// loop iteration.
//
// We make 100 attempts before giving up.
// This could happen in the following situations:
//
// 1. There is a bug preventing the index from being correctly closed, or us from detecting this.
// 2. A user of the index is keeping it open for more than 600 seconds. This could happen e.g. during a pathological search.
// This can not be caused by indexation because deleting an index happens in the scheduler itself, so cannot be concurrent with indexation.
//
// In these situations, reporting the error through a panic is in order.
let closing_event = loop {
let mut lock = self.index_map.write().unwrap();
let resize_operation = match lock.insert(uuid, BeingDeleted) {
Some(Available(index)) => break Some(index.prepare_for_closing()),
// The target index is in the middle of a resize operation.
// Wait for this operation to complete, then try again.
Some(BeingResized(resize_operation)) => resize_operation.clone(),
// The index is already being deleted or doesn't exist.
// It's OK to remove it from the map again.
_ => break None,
};
// Avoiding deadlocks: we need to drop the lock before waiting for the end of the resize, which
// will involve operations on the very map we're locking.
drop(lock);
resize_operation.wait();
match lock.start_deletion(&uuid) {
Ok(env_closing) => break env_closing,
Err(Some(reopen)) => {
// drop the lock here so that we don't synchronously wait for the index to close.
drop(lock);
tries += 1;
if tries >= 100 {
panic!("Too many attempts to close index {name} prior to deletion.")
}
let reopen = if let Some(reopen) = reopen.wait_timeout(Duration::from_secs(6)) {
reopen
} else {
continue;
};
reopen.close(&mut self.index_map.write().unwrap());
continue;
}
Err(None) => return Ok(()),
}
};
let index_map = self.index_map.clone();
@ -161,7 +189,7 @@ impl IndexMapper {
.name(String::from("index_deleter"))
.spawn(move || {
// We first wait to be sure that the previously opened index is effectively closed.
// This can take a lot of time, this is why we do that in a seperate thread.
// This can take a lot of time, this is why we do that in a separate thread.
if let Some(closing_event) = closing_event {
closing_event.wait();
}
@ -175,7 +203,7 @@ impl IndexMapper {
}
// Finally we remove the entry from the index map.
assert!(matches!(index_map.write().unwrap().remove(&uuid), Some(BeingDeleted)));
index_map.write().unwrap().end_deletion(&uuid);
})
.unwrap();
@ -195,76 +223,15 @@ impl IndexMapper {
/// - If the Index corresponding to the passed name is concurrently being deleted/resized or cannot be found in the
/// in memory hash map.
pub fn resize_index(&self, rtxn: &RoTxn, name: &str) -> Result<()> {
// fixme: factor to a function?
let uuid = self
.index_mapping
.get(rtxn, name)?
.ok_or_else(|| Error::IndexNotFound(name.to_string()))?;
// We remove the index from the in-memory index map.
let mut lock = self.index_map.write().unwrap();
// signal that will be sent when the resize operation completes
let resize_operation = Arc::new(SignalEvent::manual(false));
let index = match lock.insert(uuid, BeingResized(resize_operation)) {
Some(Available(index)) => index,
Some(previous_status) => {
lock.insert(uuid, previous_status);
panic!(
"Attempting to resize index {name} that is already being resized or deleted."
)
}
None => {
panic!("Could not find the status of index {name} in the in-memory index mapper.")
}
};
self.index_map.write().unwrap().close_for_resize(&uuid, self.index_growth_amount);
drop(lock);
let resize_succeeded = (move || {
let current_size = index.map_size()?;
let new_size = current_size * 2;
let closing_event = index.prepare_for_closing();
log::debug!("Waiting for index {name} to close");
if !closing_event.wait_timeout(std::time::Duration::from_secs(600)) {
// fail after 10 minutes waiting
panic!("Could not resize index {name} (unable to close it)");
}
log::info!("Resized index {name} from {current_size} to {new_size} bytes");
let index_path = self.base_path.join(uuid.to_string());
let index = self.create_or_open_index(&index_path, None, new_size)?;
Ok(index)
})();
// Put the map back to a consistent state.
// Even if there was an error we don't want to leave the map in an inconsistent state as it would cause
// deadlocks.
let mut lock = self.index_map.write().unwrap();
let (resize_operation, resize_succeeded) = match resize_succeeded {
Ok(index) => {
// insert the resized index
let Some(BeingResized(resize_operation)) = lock.insert(uuid, Available(index)) else {
panic!("Index state for index {name} was modified while it was being resized")
};
(resize_operation, Ok(()))
}
Err(error) => {
// there was an error, not much we can do... delete the index from the in-memory map to prevent future errors
let Some(BeingResized(resize_operation)) = lock.remove(&uuid) else {
panic!("Index state for index {name} was modified while it was being resized")
};
(resize_operation, Err(error))
}
};
// drop the lock before signaling completion so that other threads don't immediately await on the lock after waking up.
drop(lock);
resize_operation.signal();
resize_succeeded
Ok(())
}
/// Return an index, may open it if it wasn't already opened.
@ -274,47 +241,68 @@ impl IndexMapper {
.get(rtxn, name)?
.ok_or_else(|| Error::IndexNotFound(name.to_string()))?;
// we clone here to drop the lock before entering the match
let mut tries = 0;
// attempts to open the index in a loop.
//
// If the index is currently being closed, we will wait for it to be closed and retry getting it in a subsequent
// loop iteration.
//
// We make 100 attempts before giving up.
// This could happen in the following situations:
//
// 1. There is a bug preventing the index from being correctly closed, or us from detecting it was.
// 2. A user of the index is keeping it open for more than 600 seconds. This could happen e.g. during a long indexation,
// a pathological search, and so on.
//
// In these situations, reporting the error through a panic is in order.
let index = loop {
let index = self.index_map.read().unwrap().get(&uuid).cloned();
tries += 1;
if tries > 100 {
panic!("Too many spurious wake ups while trying to open the index {name}");
}
// we get the index here to drop the lock before entering the match
let index = self.index_map.read().unwrap().get(&uuid);
match index {
Some(Available(index)) => break index,
Some(BeingResized(ref resize_operation)) => {
Available(index) => break index,
Closing(reopen) => {
// Avoiding deadlocks: no lock taken while doing this operation.
resize_operation.wait();
let reopen = if let Some(reopen) = reopen.wait_timeout(Duration::from_secs(6)) {
reopen
} else {
continue;
};
let index_path = self.base_path.join(uuid.to_string());
// take the lock to reopen the environment.
reopen.reopen(&mut self.index_map.write().unwrap(), &index_path)?;
continue;
}
Some(BeingDeleted) => return Err(Error::IndexNotFound(name.to_string())),
BeingDeleted => return Err(Error::IndexNotFound(name.to_string())),
// since we're lazy, it's possible that the index has not been opened yet.
None => {
Missing => {
let mut index_map = self.index_map.write().unwrap();
// between the read lock and the write lock it's not impossible
// that someone already opened the index (eg if two search happens
// that someone already opened the index (eg if two searches happen
// at the same time), thus before opening it we check a second time
// if it's not already there.
// Since there is a good chance it's not already there we can use
// the entry method.
match index_map.entry(uuid) {
Entry::Vacant(entry) => {
match index_map.get(&uuid) {
Missing => {
let index_path = self.base_path.join(uuid.to_string());
let index =
self.create_or_open_index(&index_path, None, self.index_size)?;
entry.insert(Available(index.clone()));
break index;
break index_map.create(
&uuid,
&index_path,
None,
self.index_base_map_size,
)?;
}
Entry::Occupied(entry) => match entry.get() {
Available(index) => break index.clone(),
BeingResized(resize_operation) => {
// Avoiding the deadlock: we drop the lock before waiting
let resize_operation = resize_operation.clone();
drop(index_map);
resize_operation.wait();
continue;
}
BeingDeleted => return Err(Error::IndexNotFound(name.to_string())),
},
Available(index) => break index,
Closing(_) => {
// the reopening will be handled in the next loop operation
continue;
}
BeingDeleted => return Err(Error::IndexNotFound(name.to_string())),
}
}
}
@ -323,18 +311,38 @@ impl IndexMapper {
Ok(index)
}
/// Return all indexes, may open them if they weren't already opened.
pub fn indexes(&self, rtxn: &RoTxn) -> Result<Vec<(String, Index)>> {
/// Attempts `f` for each index that exists in the index mapper.
///
/// It is preferable to use this function rather than a loop that opens all indexes, as a way to avoid having all indexes opened,
/// which is unsupported in general.
///
/// Since `f` is allowed to return a result, and `Index` is cloneable, it is still possible to wrongly build e.g. a vector of
/// all the indexes, but this function makes it harder and so less likely to do accidentally.
pub fn try_for_each_index<U, V>(
&self,
rtxn: &RoTxn,
mut f: impl FnMut(&str, &Index) -> Result<U>,
) -> Result<V>
where
V: FromIterator<U>,
{
self.index_mapping
.iter(rtxn)?
.map(|ret| {
ret.map_err(Error::from).and_then(|(name, _)| {
self.index(rtxn, name).map(|index| (name.to_string(), index))
})
.map(|res| {
res.map_err(Error::from)
.and_then(|(name, _)| self.index(rtxn, name).and_then(|index| f(name, &index)))
})
.collect()
}
/// Return the name of all indexes without opening them.
pub fn index_names(&self, rtxn: &RoTxn) -> Result<Vec<String>> {
self.index_mapping
.iter(rtxn)?
.map(|res| res.map_err(Error::from).map(|(name, _)| name.to_string()))
.collect()
}
/// Swap two index names.
pub fn swap(&self, wtxn: &mut RwTxn, lhs: &str, rhs: &str) -> Result<()> {
let lhs_uuid = self

2
index-scheduler/src/insta_snapshot.rs
View File

@ -254,6 +254,6 @@ pub fn snapshot_canceled_by(
snap
}
pub fn snapshot_index_mapper(rtxn: &RoTxn, mapper: &IndexMapper) -> String {
let names = mapper.indexes(rtxn).unwrap().into_iter().map(|(n, _)| n).collect::<Vec<_>>();
let names = mapper.index_names(rtxn).unwrap();
format!("{names:?}")
}

143
index-scheduler/src/lib.rs
View File

@ -24,6 +24,7 @@ pub mod error;
mod index_mapper;
#[cfg(test)]
mod insta_snapshot;
mod lru;
mod utils;
mod uuid_codec;
@ -31,7 +32,7 @@ pub type Result<T> = std::result::Result<T, Error>;
pub type TaskId = u32;
use std::ops::{Bound, RangeBounds};
use std::path::PathBuf;
use std::path::{Path, PathBuf};
use std::sync::atomic::AtomicBool;
use std::sync::atomic::Ordering::Relaxed;
use std::sync::{Arc, RwLock};
@ -229,8 +230,12 @@ pub struct IndexSchedulerOptions {
pub dumps_path: PathBuf,
/// The maximum size, in bytes, of the task index.
pub task_db_size: usize,
/// The maximum size, in bytes, of each meilisearch index.
pub index_size: usize,
/// The size, in bytes, with which a meilisearch index is opened the first time of each meilisearch index.
pub index_base_map_size: usize,
/// The size, in bytes, by which the map size of an index is increased when it resized due to being full.
pub index_growth_amount: usize,
/// The number of indexes that can be concurrently opened in memory.
pub index_count: usize,
/// Configuration used during indexing for each meilisearch index.
pub indexer_config: IndexerConfig,
/// Set to `true` iff the index scheduler is allowed to automatically
@ -360,9 +365,25 @@ impl IndexScheduler {
std::fs::create_dir_all(&options.indexes_path)?;
std::fs::create_dir_all(&options.dumps_path)?;
let task_db_size = clamp_to_page_size(options.task_db_size);
let budget = if options.indexer_config.skip_index_budget {
IndexBudget {
map_size: options.index_base_map_size,
index_count: options.index_count,
task_db_size,
}
} else {
Self::index_budget(
&options.tasks_path,
options.index_base_map_size,
task_db_size,
options.index_count,
)
};
let env = heed::EnvOpenOptions::new()
.max_dbs(10)
.map_size(clamp_to_page_size(options.task_db_size))
.map_size(budget.task_db_size)
.open(options.tasks_path)?;
let file_store = FileStore::new(&options.update_file_path)?;
@ -382,7 +403,9 @@ impl IndexScheduler {
index_mapper: IndexMapper::new(
&env,
options.indexes_path,
options.index_size,
budget.map_size,
options.index_growth_amount,
budget.index_count,
options.indexer_config,
)?,
env,
@ -406,6 +429,65 @@ impl IndexScheduler {
Ok(this)
}
fn index_budget(
tasks_path: &Path,
base_map_size: usize,
mut task_db_size: usize,
max_index_count: usize,
) -> IndexBudget {
let budget = utils::dichotomic_search(base_map_size, |map_size| {
Self::is_good_heed(tasks_path, map_size)
});
log::debug!("memmap budget: {budget}B");
let mut budget = budget / 2;
if task_db_size > (budget / 2) {
task_db_size = clamp_to_page_size(budget * 2 / 5);
log::debug!(
"Decreasing max size of task DB to {task_db_size}B due to constrained memory space"
);
}
budget -= task_db_size;
// won't be mutated again
let budget = budget;
let task_db_size = task_db_size;
log::debug!("index budget: {budget}B");
let mut index_count = budget / base_map_size;
if index_count < 2 {
// take a bit less than half than the budget to make sure we can always afford to open an index
let map_size = (budget * 2) / 5;
// single index of max budget
log::debug!("1 index of {map_size}B can be opened simultaneously.");
return IndexBudget { map_size, index_count: 1, task_db_size };
}
// give us some space for an additional index when the cache is already full
// decrement is OK because index_count >= 2.
index_count -= 1;
if index_count > max_index_count {
index_count = max_index_count;
}
log::debug!("Up to {index_count} indexes of {base_map_size}B opened simultaneously.");
IndexBudget { map_size: base_map_size, index_count, task_db_size }
}
fn is_good_heed(tasks_path: &Path, map_size: usize) -> bool {
if let Ok(env) =
heed::EnvOpenOptions::new().map_size(clamp_to_page_size(map_size)).open(tasks_path)
{
env.prepare_for_closing().wait();
true
} else {
// We're treating all errors equally here, not only allocation errors.
// This means there's a possiblity for the budget to lower due to errors different from allocation errors.
// For persistent errors, this is OK as long as the task db is then reopened normally without ignoring the error this time.
// For transient errors, this could lead to an instance with too low a budget.
// However transient errors are: 1) less likely than persistent errors 2) likely to cause other issues down the line anyway.
false
}
}
pub fn read_txn(&self) -> Result<RoTxn> {
self.env.read_txn().map_err(|e| e.into())
}
@ -459,15 +541,42 @@ impl IndexScheduler {
///
/// * If the index wasn't opened before, the index will be opened.
/// * If the index doesn't exist on disk, the `IndexNotFoundError` is thrown.
///
/// ### Note
///
/// As an `Index` requires a large swath of the virtual memory address space, correct usage of an `Index` does not
/// keep its handle for too long.
///
/// Some configurations also can't reasonably open multiple indexes at once.
/// If you need to fetch information from or perform an action on all indexes,
/// see the `try_for_each_index` function.
pub fn index(&self, name: &str) -> Result<Index> {
let rtxn = self.env.read_txn()?;
self.index_mapper.index(&rtxn, name)
}
/// Return and open all the indexes.
pub fn indexes(&self) -> Result<Vec<(String, Index)>> {
/// Return the name of all indexes without opening them.
pub fn index_names(self) -> Result<Vec<String>> {
let rtxn = self.env.read_txn()?;
self.index_mapper.indexes(&rtxn)
self.index_mapper.index_names(&rtxn)
}
/// Attempts `f` for each index that exists known to the index scheduler.
///
/// It is preferable to use this function rather than a loop that opens all indexes, as a way to avoid having all indexes opened,
/// which is unsupported in general.
///
/// Since `f` is allowed to return a result, and `Index` is cloneable, it is still possible to wrongly build e.g. a vector of
/// all the indexes, but this function makes it harder and so less likely to do accidentally.
///
/// If many indexes exist, this operation can take time to complete (in the order of seconds for a 1000 of indexes) as it needs to open
/// all the indexes.
pub fn try_for_each_index<U, V>(&self, f: impl FnMut(&str, &Index) -> Result<U>) -> Result<V>
where
V: FromIterator<U>,
{
let rtxn = self.env.read_txn()?;
self.index_mapper.try_for_each_index(&rtxn, f)
}
/// Return the task ids matched by the given query from the index scheduler's point of view.
@ -1109,6 +1218,16 @@ pub enum TickOutcome {
WaitForSignal,
}
/// How many indexes we can afford to have open simultaneously.
struct IndexBudget {
/// Map size of an index.
map_size: usize,
/// Maximum number of simultaneously opened indexes.
index_count: usize,
/// For very constrained systems we might need to reduce the base task_db_size so we can accept at least one index.
task_db_size: usize,
}
#[cfg(test)]
mod tests {
use std::io::{BufWriter, Seek, Write};
@ -1154,6 +1273,8 @@ mod tests {
let tempdir = TempDir::new().unwrap();
let (sender, receiver) = crossbeam::channel::bounded(0);
let indexer_config = IndexerConfig { skip_index_budget: true, ..Default::default() };
let options = IndexSchedulerOptions {
version_file_path: tempdir.path().join(VERSION_FILE_NAME),
auth_path: tempdir.path().join("auth"),
@ -1163,8 +1284,10 @@ mod tests {
snapshots_path: tempdir.path().join("snapshots"),
dumps_path: tempdir.path().join("dumps"),
task_db_size: 1000 * 1000, // 1 MB, we don't use MiB on purpose.
index_size: 1000 * 1000, // 1 MB, we don't use MiB on purpose.
indexer_config: IndexerConfig::default(),
index_base_map_size: 1000 * 1000, // 1 MB, we don't use MiB on purpose.
index_growth_amount: 1000 * 1000, // 1 MB
index_count: 5,
indexer_config,
autobatching_enabled,
};

203
index-scheduler/src/lru.rs Normal file
View File

@ -0,0 +1,203 @@
//! Thread-safe `Vec`-backend LRU cache using [`std::sync::atomic::AtomicU64`] for synchronization.
use std::sync::atomic::{AtomicU64, Ordering};
/// Thread-safe `Vec`-backend LRU cache
#[derive(Debug)]
pub struct Lru<T> {
data: Vec<(AtomicU64, T)>,
generation: AtomicU64,
cap: usize,
}
impl<T> Lru<T> {
/// Creates a new LRU cache with the specified capacity.
///
/// The capacity is allocated up-front, and will never change through a [`Self::put`] operation.
///
/// # Panics
///
/// - If the capacity is 0.
/// - If the capacity exceeds `isize::MAX` bytes.
pub fn new(cap: usize) -> Self {
assert_ne!(cap, 0, "The capacity of a cache cannot be 0");
Self {
// Note: since the element of the vector contains an AtomicU64, it is definitely not zero-sized so cap will never be usize::MAX.
data: Vec::with_capacity(cap),
generation: AtomicU64::new(0),
cap,
}
}
/// The capacity of this LRU cache, that is the maximum number of elements it can hold before evicting elements from the cache.
///
/// The cache will contain at most this number of elements at any given time.
pub fn capacity(&self) -> usize {
self.cap
}
fn next_generation(&self) -> u64 {
// Acquire so this "happens-before" any potential store to a data cell (with Release ordering)
let generation = self.generation.fetch_add(1, Ordering::Acquire);
generation + 1
}
fn next_generation_mut(&mut self) -> u64 {
let generation = self.generation.get_mut();
*generation += 1;
*generation
}
/// Add a value in the cache, evicting an older value if necessary.
///
/// If a value was evicted from the cache, it is returned.
///
/// # Complexity
///
/// - If the cache is full, then linear in the capacity.
/// - Otherwise constant.
pub fn put(&mut self, value: T) -> Option<T> {
// no need for a memory fence: we assume that whichever mechanism provides us synchronization
// (very probably, a RwLock) takes care of fencing for us.
let next_generation = self.next_generation_mut();
let evicted = if self.is_full() { self.pop() } else { None };
self.data.push((AtomicU64::new(next_generation), value));
evicted
}
/// Evict the oldest value from the cache.
///
/// If the cache is empty, `None` will be returned.
///
/// # Complexity
///
/// - Linear in the capacity of the cache.
pub fn pop(&mut self) -> Option<T> {
// Don't use `Iterator::min_by_key` that provides shared references to its elements,
// so that we can get an exclusive one.
// This allows to handles the `AtomicU64`s as normal integers without using atomic instructions.
let mut min_generation_index = None;
for (index, (generation, _)) in self.data.iter_mut().enumerate() {
let generation = *generation.get_mut();
if let Some((_, min_generation)) = min_generation_index {
if min_generation > generation {
min_generation_index = Some((index, generation));
}
} else {
min_generation_index = Some((index, generation))
}
}
min_generation_index.map(|(min_index, _)| self.data.swap_remove(min_index).1)
}
/// The current number of elements in the cache.
///
/// This value is guaranteed to be less than or equal to [`Self::capacity`].
pub fn len(&self) -> usize {
self.data.len()
}
/// Returns `true` if putting any additional element in the cache would cause the eviction of an element.
pub fn is_full(&self) -> bool {
self.len() == self.capacity()
}
}
pub struct LruMap<K, V>(Lru<(K, V)>);
impl<K, V> LruMap<K, V>
where
K: Eq,
{
/// Creates a new LRU cache map with the specified capacity.
///
/// The capacity is allocated up-front, and will never change through a [`Self::insert`] operation.
///
/// # Panics
///
/// - If the capacity is 0.
/// - If the capacity exceeds `isize::MAX` bytes.
pub fn new(cap: usize) -> Self {
Self(Lru::new(cap))
}
/// Gets a value in the cache map by its key.
///
/// If no value matches, `None` will be returned.
///
/// # Complexity
///
/// - Linear in the capacity of the cache.
pub fn get(&self, key: &K) -> Option<&V> {
for (generation, (candidate, value)) in self.0.data.iter() {
if key == candidate {
generation.store(self.0.next_generation(), Ordering::Release);
return Some(value);
}
}
None
}
/// Gets a value in the cache map by its key.
///
/// If no value matches, `None` will be returned.
///
/// # Complexity
///
/// - Linear in the capacity of the cache.
pub fn get_mut(&mut self, key: &K) -> Option<&mut V> {
let next_generation = self.0.next_generation_mut();
for (generation, (candidate, value)) in self.0.data.iter_mut() {
if key == candidate {
*generation.get_mut() = next_generation;
return Some(value);
}
}
None
}
/// Inserts a value in the cache map by its key, replacing any existing value and returning any evicted value.
///
/// # Complexity
///
/// - Linear in the capacity of the cache.
pub fn insert(&mut self, key: K, mut value: V) -> InsertionOutcome<K, V> {
match self.get_mut(&key) {
Some(old_value) => {
std::mem::swap(old_value, &mut value);
InsertionOutcome::Replaced(value)
}
None => match self.0.put((key, value)) {
Some((key, value)) => InsertionOutcome::Evicted(key, value),
None => InsertionOutcome::InsertedNew,
},
}
}
/// Removes an element from the cache map by its key, returning its value.
///
/// Returns `None` if there was no element with this key in the cache.
///
/// # Complexity
///
/// - Linear in the capacity of the cache.
pub fn remove(&mut self, key: &K) -> Option<V> {
for (index, (_, (candidate, _))) in self.0.data.iter_mut().enumerate() {
if key == candidate {
return Some(self.0.data.swap_remove(index).1 .1);
}
}
None
}
}
/// The result of an insertion in a LRU map.
pub enum InsertionOutcome<K, V> {
/// The key was not in the cache, the key-value pair has been inserted.
InsertedNew,
/// The key was not in the cache and an old key-value pair was evicted from the cache to make room for its insertions.
Evicted(K, V),
/// The key was already in the cache map, its value has been updated.
Replaced(V),
}

34
index-scheduler/src/utils.rs
View File

@ -538,3 +538,37 @@ impl IndexScheduler {
}
}
}
pub fn dichotomic_search(start_point: usize, mut is_good: impl FnMut(usize) -> bool) -> usize {
let mut biggest_good = None;
let mut smallest_bad = None;
let mut current = start_point;
loop {
let is_good = is_good(current);
(biggest_good, smallest_bad, current) = match (biggest_good, smallest_bad, is_good) {
(None, None, false) => (None, Some(current), current / 2),
(None, None, true) => (Some(current), None, current * 2),
(None, Some(smallest_bad), true) => {
(Some(current), Some(smallest_bad), (current + smallest_bad) / 2)
}
(None, Some(_), false) => (None, Some(current), current / 2),
(Some(_), None, true) => (Some(current), None, current * 2),
(Some(biggest_good), None, false) => {
(Some(biggest_good), Some(current), (biggest_good + current) / 2)
}
(Some(_), Some(smallest_bad), true) => {
(Some(current), Some(smallest_bad), (smallest_bad + current) / 2)
}
(Some(biggest_good), Some(_), false) => {
(Some(biggest_good), Some(current), (biggest_good + current) / 2)
}
};
if current == 0 {
return current;
}
if smallest_bad.is_some() && biggest_good.is_some() && biggest_good >= Some(current) {
return current;
}
}
}

3
meilisearch/src/analytics/segment_analytics.rs
View File

@ -292,7 +292,8 @@ impl From<Opt> for Infos {
ScheduleSnapshot::Enabled(interval) => Some(interval),
};
let IndexerOpts { max_indexing_memory, max_indexing_threads } = indexer_options;
let IndexerOpts { max_indexing_memory, max_indexing_threads, skip_index_budget: _ } =
indexer_options;
// We're going to override every sensible information.
// We consider information sensible if it contains a path, an address, or a key.

32
meilisearch/src/lib.rs
View File

@ -45,6 +45,34 @@ use option::ScheduleSnapshot;
use crate::error::MeilisearchHttpError;
/// Default number of simultaneously opened indexes.
///
/// This value is used when dynamic computation of how many indexes can be opened at once was skipped (e.g., in tests).
///
/// Lower for Windows that dedicates a smaller virtual address space to processes.
///
/// The value was chosen this way:
///
/// - Windows provides a small virtual address space of about 10TiB to processes.
/// - The chosen value allows for indexes to use the default map size of 2TiB safely.
#[cfg(windows)]
const DEFAULT_INDEX_COUNT: usize = 4;
/// Default number of simultaneously opened indexes.
///
/// This value is used when dynamic computation of how many indexes can be opened at once was skipped (e.g., in tests).
///
/// The higher, the better for avoiding reopening indexes.
///
/// The value was chosen this way:
///
/// - Opening an index consumes a file descriptor.
/// - The default on many unices is about 256 file descriptors for a process.
/// - 100 is a little bit less than half this value.
/// - The chosen value allows for indexes to use the default map size of 2TiB safely.
#[cfg(not(windows))]
const DEFAULT_INDEX_COUNT: usize = 20;
/// Check if a db is empty. It does not provide any information on the
/// validity of the data in it.
/// We consider a database as non empty when it's a non empty directory.
@ -206,9 +234,11 @@ fn open_or_create_database_unchecked(
snapshots_path: opt.snapshot_dir.clone(),
dumps_path: opt.dump_dir.clone(),
task_db_size: opt.max_task_db_size.get_bytes() as usize,
index_size: opt.max_index_size.get_bytes() as usize,
index_base_map_size: opt.max_index_size.get_bytes() as usize,
indexer_config: (&opt.indexer_options).try_into()?,
autobatching_enabled: true,
index_growth_amount: byte_unit::Byte::from_str("10GiB").unwrap().get_bytes() as usize,
index_count: DEFAULT_INDEX_COUNT,
})?)
};

22
meilisearch/src/option.rs
View File

@ -65,11 +65,11 @@ const MEILI_MAX_INDEXING_THREADS: &str = "MEILI_MAX_INDEXING_THREADS";
const DEFAULT_LOG_EVERY_N: usize = 100_000;
// Each environment (index and task-db) is taking space in the virtual address space.
//
// The size of the virtual address space is limited by the OS. About 100TB for Linux and about 10TB for Windows.
// This means that the number of indexes is limited to about 200 for Linux and about 20 for Windows.
pub const INDEX_SIZE: u64 = 536_870_912_000; // 500 GiB
pub const TASK_DB_SIZE: u64 = 10_737_418_240; // 10 GiB
// Ideally, indexes can occupy 2TiB each to avoid having to manually resize them.
// The actual size of the virtual address space is computed at startup to determine how many 2TiB indexes can be
// opened simultaneously.
pub const INDEX_SIZE: u64 = 2 * 1024 * 1024 * 1024 * 1024; // 2 TiB
pub const TASK_DB_SIZE: u64 = 10 * 1024 * 1024 * 1024; // 10 GiB
#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize)]
#[serde(rename_all = "UPPERCASE")]
@ -494,12 +494,21 @@ pub struct IndexerOpts {
#[clap(long, env = MEILI_MAX_INDEXING_THREADS, default_value_t)]
#[serde(default)]
pub max_indexing_threads: MaxThreads,
/// Whether or not we want to determine the budget of virtual memory address space we have available dynamically
/// (the default), or statically.
///
/// Determining the budget of virtual memory address space dynamically takes some time on some systems (such as macOS)
/// and may make tests non-deterministic, so we want to skip it in tests.
#[clap(skip)]
#[serde(skip)]
pub skip_index_budget: bool,
}
impl IndexerOpts {
/// Exports the values to their corresponding env vars if they are not set.
pub fn export_to_env(self) {
let IndexerOpts { max_indexing_memory, max_indexing_threads } = self;
let IndexerOpts { max_indexing_memory, max_indexing_threads, skip_index_budget: _ } = self;
if let Some(max_indexing_memory) = max_indexing_memory.0 {
export_to_env_if_not_present(
MEILI_MAX_INDEXING_MEMORY,
@ -527,6 +536,7 @@ impl TryFrom<&IndexerOpts> for IndexerConfig {
max_memory: other.max_indexing_memory.map(|b| b.get_bytes() as usize),
thread_pool: Some(thread_pool),
max_positions_per_attributes: None,
skip_index_budget: other.skip_index_budget,
..Default::default()
})
}

18
meilisearch/src/routes/indexes/mod.rs
View File

@ -61,6 +61,8 @@ pub struct IndexView {
impl IndexView {
fn new(uid: String, index: &Index) -> Result<IndexView, milli::Error> {
// It is important that this function does not keep the Index handle or a clone of it, because
// `list_indexes` relies on this property to avoid opening all indexes at once.
let rtxn = index.read_txn()?;
Ok(IndexView {
uid,
@ -90,13 +92,15 @@ pub async fn list_indexes(
paginate: AwebQueryParameter<ListIndexes, DeserrQueryParamError>,
) -> Result<HttpResponse, ResponseError> {
let filters = index_scheduler.filters();
let indexes: Vec<_> = index_scheduler.indexes()?;
let indexes = indexes
.into_iter()
.filter(|(name, _)| filters.is_index_authorized(name))
.map(|(name, index)| IndexView::new(name, &index))
.collect::<Result<Vec<_>, _>>()?;
let indexes: Vec<Option<IndexView>> =
index_scheduler.try_for_each_index(|uid, index| -> Result<Option<IndexView>, _> {
if !filters.is_index_authorized(uid) {
return Ok(None);
}
Ok(Some(IndexView::new(uid.to_string(), index)?))
})?;
// Won't cause to open all indexes because IndexView doesn't keep the `Index` opened.
let indexes: Vec<IndexView> = indexes.into_iter().flatten().collect();
let ret = paginate.as_pagination().auto_paginate_sized(indexes.into_iter());
debug!("returns: {:?}", ret);

11
meilisearch/src/routes/mod.rs
View File

@ -261,9 +261,9 @@ pub fn create_all_stats(
)?;
// accumulate the size of each indexes
let processing_index = processing_task.first().and_then(|task| task.index_uid());
for (name, index) in index_scheduler.indexes()? {
if !filters.is_index_authorized(&name) {
continue;
index_scheduler.try_for_each_index(|name, index| {
if !filters.is_index_authorized(name) {
return Ok(());
}
database_size += index.on_disk_size()?;
@ -278,8 +278,9 @@ pub fn create_all_stats(
let updated_at = index.updated_at(&rtxn)?;
last_task = last_task.map_or(Some(updated_at), |last| Some(last.max(updated_at)));
indexes.insert(name, stats);
}
indexes.insert(name.to_string(), stats);
Ok(())
})?;
database_size += index_scheduler.size()?;
database_size += auth_controller.size()?;

1
meilisearch/tests/common/server.rs
View File

@ -205,6 +205,7 @@ pub fn default_settings(dir: impl AsRef<Path>) -> Opt {
indexer_options: IndexerOpts {
// memory has to be unlimited because several meilisearch are running in test context.
max_indexing_memory: MaxMemory::unlimited(),
skip_index_budget: true,
..Parser::parse_from(None as Option<&str>)
},
#[cfg(feature = "metrics")]

2
milli/src/update/indexer_config.rs
View File

@ -11,6 +11,7 @@ pub struct IndexerConfig {
pub chunk_compression_level: Option<u32>,
pub thread_pool: Option<ThreadPool>,
pub max_positions_per_attributes: Option<u32>,
pub skip_index_budget: bool,
}
impl Default for IndexerConfig {
@ -24,6 +25,7 @@ impl Default for IndexerConfig {
chunk_compression_level: None,
thread_pool: None,
max_positions_per_attributes: None,
skip_index_budget: false,
}
}
}