refactor: move `querier::cache_system` into its own crate (#4592)

Cargo.lock

@@ -587,6 +587,22 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "cache_system"
+version = "0.1.0"
+dependencies = [
+ "async-trait",
+ "criterion",
+ "futures",
+ "iox_time",
+ "observability_deps",
+ "parking_lot 0.12.0",
+ "proptest",
+ "rand",
+ "tokio",
+ "workspace-hack",
+]
+
 [[package]]
 name = "cast"
 version = "0.2.7"
@@ -4097,8 +4113,8 @@ dependencies = [
  "assert_matches",
  "async-trait",
  "backoff 0.1.0",
+ "cache_system",
  "client_util",
- "criterion",
  "data_types",
  "datafusion 0.1.0",
  "datafusion_util",
@@ -4116,7 +4132,6 @@ dependencies = [
  "parquet_file",
  "pin-project",
  "predicate",
- "proptest",
  "query",
  "rand",
  "schema",

Cargo.toml

@@ -3,6 +3,7 @@
 members = [
     "arrow_util",
     "backoff",
+    "cache_system",
     "clap_blocks",
     "client_util",
     "compactor",

cache_system/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "cache_system"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+async-trait = "0.1.53"
+futures = "0.3"
+iox_time = { path = "../iox_time" }
+observability_deps = { path = "../observability_deps" }
+parking_lot = "0.12"
+tokio = { version = "1.18", features = ["macros", "parking_lot", "rt-multi-thread", "sync", "time"] }
+workspace-hack = { path = "../workspace-hack"}
+
+[dev-dependencies]
+criterion = "0.3"
+proptest = { version = "1", default_features = false, features = ["std"] }
+rand = "0.8.3"
+
+[[bench]]
+name = "addressable_heap"
+harness = false

cache_system/benches/addressable_heap.rs

@@ -1,10 +1,10 @@
 use std::mem::size_of;
 
+use cache_system::backend::addressable_heap::AddressableHeap;
 use criterion::{
     criterion_group, criterion_main, measurement::WallTime, AxisScale, BatchSize, BenchmarkGroup,
     BenchmarkId, Criterion, PlotConfiguration, SamplingMode,
 };
-use querier::AddressableHeap;
 use rand::{prelude::SliceRandom, thread_rng, Rng};
 
 /// Payload (`V`) for testing.

cache_system/src/backend/addressable_heap.rs

@@ -1,3 +1,4 @@
+//! Implementation of an [`AddressableHeap`].
 use std::{
     collections::{HashMap, VecDeque},
     hash::Hash,

cache_system/src/backend/dual.rs

@@ -1,3 +1,4 @@
+//! Cross-populated two caches.
 use std::{any::Any, fmt::Debug, hash::Hash, sync::Arc};
 
 use parking_lot::Mutex;
@@ -310,7 +311,7 @@ mod tests {
 
     #[test]
     fn test_generic1() {
-        use crate::cache_system::backend::test_util::test_generic;
+        use crate::backend::test_util::test_generic;
 
         test_generic(|| {
             let backend1 = Box::new(HashMap::<u8, String>::new());
@@ -328,7 +329,7 @@ mod tests {
 
     #[test]
     fn test_generic2() {
-        use crate::cache_system::backend::test_util::test_generic;
+        use crate::backend::test_util::test_generic;
 
         test_generic(|| {
             let backend1 = Box::new(HashMap::<i8, String>::new());

cache_system/src/backend/hash_map.rs

@@ -1,3 +1,4 @@
+//! Implements [`CacheBackend`] for [`HashMap`].
 use std::{
     any::Any,
     collections::HashMap,
@@ -43,7 +44,7 @@ mod tests {
 
     #[test]
     fn test_generic() {
-        use crate::cache_system::backend::test_util::test_generic;
+        use crate::backend::test_util::test_generic;
 
         test_generic(HashMap::new);
     }

cache_system/src/backend/lru.rs

@@ -9,7 +9,7 @@
 //!     sync::Arc,
 //! };
 //! use iox_time::SystemProvider;
-//! use querier::{
+//! use cache_system::backend::{
 //!     CacheBackend,
 //!     lru::{LruBackend, ResourcePool},
 //!     resource_consumption::{Resource, ResourceEstimator},
@@ -1114,7 +1114,7 @@ mod tests {
 
     #[test]
     fn test_generic() {
-        use crate::cache_system::backend::test_util::test_generic;
+        use crate::backend::test_util::test_generic;
 
         #[derive(Debug)]
         struct ZeroSizeProvider {}

cache_system/src/backend/mod.rs

@@ -1,3 +1,4 @@
+//! Storage backends to keep and manage cached entries.
 use std::{any::Any, fmt::Debug, hash::Hash};
 
 pub mod addressable_heap;

cache_system/src/backend/ttl.rs

@@ -1,3 +1,4 @@
+//! Time-to-live handling.
 use std::{any::Any, fmt::Debug, hash::Hash, marker::PhantomData, sync::Arc, time::Duration};
 
 use iox_time::{Time, TimeProvider};
@@ -552,7 +553,7 @@ mod tests {
 
     #[test]
     fn test_generic() {
-        use crate::cache_system::backend::test_util::test_generic;
+        use crate::backend::test_util::test_generic;
 
         test_generic(|| {
             let ttl_provider = Arc::new(NeverTtlProvider::default());

cache_system/src/driver.rs

@@ -1,3 +1,4 @@
+//! Main data structure, see [`Cache`].
 use std::{collections::HashMap, hash::Hash, sync::Arc};
 
 use futures::{

cache_system/src/lib.rs

@@ -0,0 +1,14 @@
+//! Flexible and modular cache system.
+#![deny(rustdoc::broken_intra_doc_links, rust_2018_idioms)]
+#![warn(
+    missing_copy_implementations,
+    missing_docs,
+    clippy::explicit_iter_loop,
+    clippy::future_not_send,
+    clippy::use_self,
+    clippy::clone_on_ref_ptr
+)]
+
+pub mod backend;
+pub mod driver;
+pub mod loader;

cache_system/src/loader.rs

@@ -1,8 +1,9 @@
+//! How to load new cache entries.
 use async_trait::async_trait;
 use futures::{future::BoxFuture, FutureExt};
 use std::future::Future;
 
-/// Loader for missing [`Cache`](crate::cache_system::driver::Cache) entries.
+/// Loader for missing [`Cache`](crate::driver::Cache) entries.
 #[async_trait]
 pub trait Loader: std::fmt::Debug + Send + Sync + 'static {
     /// Cache key.

querier/Cargo.toml

@@ -7,6 +7,7 @@ edition = "2021"
 arrow = "13"
 async-trait = "0.1.53"
 backoff = { path = "../backoff" }
+cache_system = { path = "../cache_system" }
 client_util = { path = "../client_util" }
 data_types = { path = "../data_types" }
 datafusion = { path = "../datafusion" }
@@ -40,12 +41,6 @@ workspace-hack = { path = "../workspace-hack"}
 [dev-dependencies]
 arrow_util = { path = "../arrow_util" }
 assert_matches = "1.5"
-criterion = "0.3"
 iox_tests = { path = "../iox_tests" }
 mutable_batch_lp = { path = "../mutable_batch_lp" }
-proptest = { version = "1", default_features = false, features = ["std"] }
 test_helpers = { path = "../test_helpers" }
-
-[[bench]]
-name = "addressable_heap"
-harness = false

querier/src/cache/namespace.rs

@@ -1,6 +1,7 @@
 //! Namespace cache.
 
-use crate::cache_system::{
+use backoff::{Backoff, BackoffConfig};
+use cache_system::{
     backend::{
         dual::dual_backends,
         ttl::{OptionalValueTtlProvider, TtlBackend},
@@ -8,7 +9,6 @@ use crate::cache_system::{
     driver::Cache,
     loader::FunctionLoader,
 };
-use backoff::{Backoff, BackoffConfig};
 use data_types::{NamespaceId, NamespaceSchema};
 use iox_catalog::interface::{get_schema_by_name, Catalog};
 use iox_time::TimeProvider;

querier/src/cache/partition.rs

@@ -1,7 +1,7 @@
 //! Partition cache.
 
-use crate::cache_system::{driver::Cache, loader::FunctionLoader};
 use backoff::{Backoff, BackoffConfig};
+use cache_system::{driver::Cache, loader::FunctionLoader};
 use data_types::{PartitionId, SequencerId};
 use iox_catalog::interface::Catalog;
 use schema::sort::SortKey;

querier/src/cache/processed_tombstones.rs

@@ -1,11 +1,11 @@
 //! Processed tombstone cache.
 
-use crate::cache_system::{
+use backoff::{Backoff, BackoffConfig};
+use cache_system::{
     backend::ttl::{TtlBackend, TtlProvider},
     driver::Cache,
     loader::FunctionLoader,
 };
-use backoff::{Backoff, BackoffConfig};
 use data_types::{ParquetFileId, TombstoneId};
 use iox_catalog::interface::Catalog;
 use iox_time::TimeProvider;

querier/src/cache/table.rs

@@ -1,6 +1,7 @@
 //! Table cache.
 
-use crate::cache_system::{
+use backoff::{Backoff, BackoffConfig};
+use cache_system::{
     backend::{
         dual::dual_backends,
         ttl::{OptionalValueTtlProvider, TtlBackend},
@@ -8,7 +9,6 @@ use crate::cache_system::{
     driver::Cache,
     loader::FunctionLoader,
 };
-use backoff::{Backoff, BackoffConfig};
 use data_types::{NamespaceId, Table, TableId};
 use iox_catalog::interface::Catalog;
 use iox_time::TimeProvider;

querier/src/cache_system/mod.rs

@@ -1,3 +0,0 @@
-pub mod backend;
-pub mod driver;
-pub mod loader;

querier/src/lib.rs

@@ -10,7 +10,6 @@
 )]
 
 pub mod cache;
-mod cache_system;
 pub mod chunk;
 mod database;
 mod handler;
@@ -36,11 +35,3 @@ pub use ingester::{
 };
 pub use namespace::QuerierNamespace;
 pub use server::QuerierServer;
-
-// for benchmarks
-pub use cache_system::backend::addressable_heap::AddressableHeap;
-
-// for doctests
-pub use cache_system::backend::lru;
-pub use cache_system::backend::resource_consumption;
-pub use cache_system::backend::CacheBackend;