mirror of
https://github.com/meilisearch/MeiliSearch
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move index_map to file
This commit is contained in:
Louis Dureuil
parent
431782f3ee
commit
71e7900c67
370
index-scheduler/src/index_mapper/index_map.rs
Normal file
370
index-scheduler/src/index_mapper/index_map.rs
Normal file
@ -0,0 +1,370 @@
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/// the map size to use when we don't succeed in reading it in indexes.
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const DEFAULT_MAP_SIZE: usize = 10 * 1024 * 1024 * 1024; // 10 GiB
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use std::collections::BTreeMap;
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use std::path::Path;
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use std::time::Duration;
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use meilisearch_types::heed::{EnvClosingEvent, EnvOpenOptions};
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use meilisearch_types::milli::Index;
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use time::OffsetDateTime;
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use uuid::Uuid;
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use super::IndexStatus::{self, Available, BeingDeleted, Closing, Missing};
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use crate::lru::{InsertionOutcome, LruMap};
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use crate::{clamp_to_page_size, Result};
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/// Keep an internally consistent view of the open indexes in memory.
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///
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/// This view is made of an LRU cache that will evict the least frequently used indexes when new indexes are opened.
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/// Indexes that are being closed (for resizing or due to cache eviction) or deleted cannot be evicted from the cache and
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/// are stored separately.
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///
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/// This view provides operations to change the state of the index as it is known in memory:
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/// open an index (making it available for queries), close an index (specifying the new size it should be opened with),
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/// delete an index.
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///
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/// External consistency with the other bits of data of an index is provided by the `IndexMapper` parent structure.
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pub struct IndexMap {
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/// A LRU map of indexes that are in the open state and available for queries.
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available: LruMap<Uuid, Index>,
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/// A map of indexes that are not available for queries, either because they are being deleted
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/// or because they are being closed.
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///
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/// If they are being deleted, the UUID points to `None`.
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unavailable: BTreeMap<Uuid, Option<ClosingIndex>>,
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/// A monotonically increasing generation number, used to differentiate between multiple successive index closing requests.
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///
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/// Because multiple readers could be waiting on an index to close, the following could theoretically happen:
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///
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/// 1. Multiple readers wait for the index closing to occur.
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/// 2. One of them "wins the race", takes the lock and then removes the index that finished closing from the map.
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/// 3. The index is reopened, but must be closed again (such as being resized again).
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/// 4. One reader that "lost the race" in (2) wakes up and tries to take the lock and remove the index from the map.
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///
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/// In that situation, the index may or may not have finished closing. The `generation` field allows to remember which
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/// closing request was made, so the reader that "lost the race" has the old generation and will need to wait again for the index
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/// to close.
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generation: usize,
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}
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#[derive(Clone)]
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pub struct ClosingIndex {
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uuid: Uuid,
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closing_event: EnvClosingEvent,
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map_size: usize,
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generation: usize,
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}
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impl ClosingIndex {
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/// Waits for the index to be definitely closed.
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///
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/// To avoid blocking, users should relinquish their locks to the IndexMap before calling this function.
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///
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/// After the index is physically closed, the in memory map must still be updated to take this into account.
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/// To do so, a `ReopenableIndex` is returned, that can be used to either definitely close or definitely open
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/// the index without waiting anymore.
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pub fn wait_timeout(self, timeout: Duration) -> Option<ReopenableIndex> {
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self.closing_event.wait_timeout(timeout).then_some(ReopenableIndex {
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uuid: self.uuid,
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map_size: self.map_size,
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generation: self.generation,
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})
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}
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}
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pub struct ReopenableIndex {
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uuid: Uuid,
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map_size: usize,
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generation: usize,
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}
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impl ReopenableIndex {
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/// Attempts to reopen the index, which can result in the index being reopened again or not
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/// (e.g. if another thread already opened and closed the index again).
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///
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/// Use get again on the IndexMap to get the updated status.
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///
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/// Fails if the underlying index creation fails.
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///
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/// # Status table
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///
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/// | Previous Status | New Status |
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/// |-----------------|----------------------------------------------|
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/// | Missing | Missing |
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/// | BeingDeleted | BeingDeleted |
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/// | Closing | Available or Closing depending on generation |
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/// | Available | Available |
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///
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pub fn reopen(self, map: &mut IndexMap, path: &Path) -> Result<()> {
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if let Closing(reopen) = map.get(&self.uuid) {
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if reopen.generation != self.generation {
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return Ok(());
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}
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map.unavailable.remove(&self.uuid);
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map.create(&self.uuid, path, None, self.map_size)?;
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}
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Ok(())
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}
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/// Attempts to close the index, which may or may not result in the index being closed
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/// (e.g. if another thread already reopened the index again).
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///
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/// Use get again on the IndexMap to get the updated status.
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///
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/// # Status table
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///
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/// | Previous Status | New Status |
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/// |-----------------|--------------------------------------------|
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/// | Missing | Missing |
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/// | BeingDeleted | BeingDeleted |
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/// | Closing | Missing or Closing depending on generation |
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/// | Available | Available |
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pub fn close(self, map: &mut IndexMap) {
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if let Closing(reopen) = map.get(&self.uuid) {
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if reopen.generation != self.generation {
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return;
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}
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map.unavailable.remove(&self.uuid);
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}
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}
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}
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impl IndexMap {
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pub fn new(cap: usize) -> IndexMap {
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Self { unavailable: Default::default(), available: LruMap::new(cap), generation: 0 }
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}
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/// Gets the current status of an index in the map.
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///
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/// If the index is available it can be accessed from the returned status.
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pub fn get(&self, uuid: &Uuid) -> IndexStatus {
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self.available
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.get(uuid)
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.map(|index| Available(index.clone()))
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.unwrap_or_else(|| self.get_unavailable(uuid))
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}
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fn get_unavailable(&self, uuid: &Uuid) -> IndexStatus {
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match self.unavailable.get(uuid) {
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Some(Some(reopen)) => Closing(reopen.clone()),
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Some(None) => BeingDeleted,
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None => Missing,
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}
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}
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/// Attempts to create a new index that wasn't existing before.
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///
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/// # Status table
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///
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/// | Previous Status | New Status |
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/// |-----------------|------------|
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/// | Missing | Available |
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/// | BeingDeleted | panics |
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/// | Closing | panics |
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/// | Available | panics |
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///
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pub fn create(
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&mut self,
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uuid: &Uuid,
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path: &Path,
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date: Option<(OffsetDateTime, OffsetDateTime)>,
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map_size: usize,
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) -> Result<Index> {
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if !matches!(self.get_unavailable(uuid), Missing) {
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panic!("Attempt to open an index that was unavailable");
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}
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let index = create_or_open_index(path, date, map_size)?;
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match self.available.insert(*uuid, index.clone()) {
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InsertionOutcome::InsertedNew => (),
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InsertionOutcome::Evicted(evicted_uuid, evicted_index) => {
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self.close(evicted_uuid, evicted_index, 0);
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}
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InsertionOutcome::Replaced(_) => {
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panic!("Attempt to open an index that was already opened")
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}
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}
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Ok(index)
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}
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/// Increases the current generation. See documentation for this field.
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///
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/// In the unlikely event that the 2^64 generations would have been exhausted, we simply wrap-around.
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///
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/// 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
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/// to remove it from the unavailable map, and keep the reader in this frozen state for 2^64 closing of other indexes.
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///
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/// This seems overwhelmingly impossible to achieve in practice.
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fn next_generation(&mut self) -> usize {
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self.generation = self.generation.wrapping_add(1);
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self.generation
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}
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/// Attempts to close an index.
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///
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/// # Status table
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///
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/// | Previous Status | New Status |
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/// |-----------------|---------------|
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/// | Missing | Missing |
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/// | BeingDeleted | BeingDeleted |
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/// | Closing | Closing |
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/// | Available | Closing |
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///
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pub fn close_for_resize(&mut self, uuid: &Uuid, map_size_growth: usize) {
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let Some(index) = self.available.remove(uuid) else { return; };
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self.close(*uuid, index, map_size_growth);
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}
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fn close(&mut self, uuid: Uuid, index: Index, map_size_growth: usize) {
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let map_size = index.map_size().unwrap_or(DEFAULT_MAP_SIZE) + map_size_growth;
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let closing_event = index.prepare_for_closing();
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let generation = self.next_generation();
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self.unavailable
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.insert(uuid, Some(ClosingIndex { uuid, closing_event, map_size, generation }));
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}
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/// Attempts to delete and index.
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///
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/// `end_deletion` must be called just after.
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///
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/// # Status table
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///
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/// | Previous Status | New Status | Return value |
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/// |-----------------|--------------|-----------------------------|
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/// | Missing | BeingDeleted | Ok(None) |
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/// | BeingDeleted | BeingDeleted | Err(None) |
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/// | Closing | Closing | Err(Some(reopen)) |
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/// | Available | BeingDeleted | Ok(Some(env_closing_event)) |
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pub fn start_deletion(
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&mut self,
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uuid: &Uuid,
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) -> std::result::Result<Option<EnvClosingEvent>, Option<ClosingIndex>> {
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if let Some(index) = self.available.remove(uuid) {
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self.unavailable.insert(*uuid, None);
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return Ok(Some(index.prepare_for_closing()));
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}
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match self.unavailable.remove(uuid) {
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Some(Some(reopen)) => Err(Some(reopen)),
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Some(None) => Err(None),
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None => Ok(None),
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}
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}
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/// Marks that an index deletion finished.
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///
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/// Must be used after calling `start_deletion`.
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///
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/// # Status table
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///
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/// | Previous Status | New Status |
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/// |-----------------|------------|
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/// | Missing | Missing |
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/// | BeingDeleted | Missing |
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/// | Closing | panics |
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/// | Available | panics |
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pub fn end_deletion(&mut self, uuid: &Uuid) {
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assert!(
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self.available.get(uuid).is_none(),
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"Attempt to finish deletion of an index that was not being deleted"
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);
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// Do not panic if the index was Missing or BeingDeleted
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assert!(
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!matches!(self.unavailable.remove(uuid), Some(Some(_))),
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"Attempt to finish deletion of an index that was being closed"
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);
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}
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}
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/// Create or open an index in the specified path.
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/// The path *must* exist or an error will be thrown.
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fn create_or_open_index(
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path: &Path,
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date: Option<(OffsetDateTime, OffsetDateTime)>,
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map_size: usize,
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) -> Result<Index> {
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let mut options = EnvOpenOptions::new();
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options.map_size(clamp_to_page_size(map_size));
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options.max_readers(1024);
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if let Some((created, updated)) = date {
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Ok(Index::new_with_creation_dates(options, path, created, updated)?)
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} else {
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Ok(Index::new(options, path)?)
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}
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}
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/// Putting the tests of the LRU down there so we have access to the cache's private members
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#[cfg(test)]
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mod tests {
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use meilisearch_types::heed::Env;
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use meilisearch_types::Index;
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use uuid::Uuid;
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use super::super::IndexMapper;
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use crate::tests::IndexSchedulerHandle;
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use crate::utils::clamp_to_page_size;
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use crate::IndexScheduler;
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impl IndexMapper {
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fn test() -> (Self, Env, IndexSchedulerHandle) {
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let (index_scheduler, handle) = IndexScheduler::test(true, vec![]);
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(index_scheduler.index_mapper, index_scheduler.env, handle)
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}
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}
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fn check_first_unavailable(mapper: &IndexMapper, expected_uuid: Uuid, is_closing: bool) {
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let index_map = mapper.index_map.read().unwrap();
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let (uuid, state) = index_map.unavailable.first_key_value().unwrap();
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assert_eq!(uuid, &expected_uuid);
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assert_eq!(state.is_some(), is_closing);
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}
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#[test]
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fn evict_indexes() {
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let (mapper, env, _handle) = IndexMapper::test();
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let mut uuids = vec![];
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// LRU cap + 1
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for i in 0..(5 + 1) {
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let index_name = format!("index-{i}");
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let wtxn = env.write_txn().unwrap();
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mapper.create_index(wtxn, &index_name, None).unwrap();
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let txn = env.read_txn().unwrap();
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uuids.push(mapper.index_mapping.get(&txn, &index_name).unwrap().unwrap());
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}
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// index-0 was evicted
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check_first_unavailable(&mapper, uuids[0], true);
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// get back the evicted index
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let wtxn = env.write_txn().unwrap();
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mapper.create_index(wtxn, "index-0", None).unwrap();
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// Least recently used is now index-1
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check_first_unavailable(&mapper, uuids[1], true);
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}
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#[test]
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fn resize_index() {
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let (mapper, env, _handle) = IndexMapper::test();
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let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
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assert_index_size(index, mapper.index_base_map_size);
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mapper.resize_index(&env.read_txn().unwrap(), "index").unwrap();
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let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
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assert_index_size(index, mapper.index_base_map_size + mapper.index_growth_amount);
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mapper.resize_index(&env.read_txn().unwrap(), "index").unwrap();
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let index = mapper.create_index(env.write_txn().unwrap(), "index", None).unwrap();
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assert_index_size(index, mapper.index_base_map_size + mapper.index_growth_amount * 2);
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}
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fn assert_index_size(index: Index, expected: usize) {
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let expected = clamp_to_page_size(expected);
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let index_map_size = index.map_size().unwrap();
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assert_eq!(index_map_size, expected);
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}
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}
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@ -16,6 +16,8 @@ use self::IndexStatus::{Available, BeingDeleted, Closing, Missing};
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use crate::uuid_codec::UuidCodec;
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use crate::{Error, Result};
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mod index_map;
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const INDEX_MAPPING: &str = "index-mapping";
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/// Structure managing meilisearch's indexes.
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@ -60,379 +62,6 @@ pub struct IndexMapper {
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pub indexer_config: Arc<IndexerConfig>,
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}
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mod index_map {
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/// the map size to use when we don't succeed in reading it in indexes.
|
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const DEFAULT_MAP_SIZE: usize = 10 * 1024 * 1024 * 1024; // 10 GiB
|
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|
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use std::collections::BTreeMap;
|
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use std::path::Path;
|
||||
use std::time::Duration;
|
||||
|
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use meilisearch_types::heed::{EnvClosingEvent, EnvOpenOptions};
|
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use meilisearch_types::milli::Index;
|
||||
use time::OffsetDateTime;
|
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use uuid::Uuid;
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|
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use super::IndexStatus::{self, Available, BeingDeleted, Closing, Missing};
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use crate::lru::{InsertionOutcome, LruMap};
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use crate::{clamp_to_page_size, Result};
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||||
|
||||
/// 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);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Whether the index is available for use or is forbidden to be inserted back in the index map
|
||||
#[allow(clippy::large_enum_variant)]
|
||||
#[derive(Clone)]
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user