In-memory Engine: integrate hybrid engine with TiKV (#16132)

ref #16141

Integrate hybrid engine with TiKV. User can choose to use hybrid engine by set `memory_engine_enabled` in TiKV config.

Signed-off-by: SpadeA-Tang <u6748471@anu.edu.au>

Cargo.toml

@@ -129,6 +129,7 @@ raftstore = { workspace = true, features = ["engine_rocks"] }
 raftstore-v2 = { workspace = true }
 rand = "0.7.3"
 regex = "1.3"
+region_cache_memory_engine = { workspace = true }
 resource_control = { workspace = true }
 resource_metering = { workspace = true }
 rev_lines = "0.2.1"
@@ -321,6 +322,7 @@ encryption_export = { path = "components/encryption/export" }
 engine_panic = { path = "components/engine_panic" }
 engine_rocks = { path = "components/engine_rocks" }
 hybrid_engine = { path = "components/hybrid_engine" }
+region_cache_memory_engine = { path = "components/region_cache_memory_engine" }
 engine_rocks_helper = { path = "components/engine_rocks_helper" }
 engine_test = { path = "components/engine_test", default-features = false }
 engine_traits = { path = "components/engine_traits" }

components/engine_panic/src/misc.rs

@@ -129,4 +129,9 @@ impl MiscExt for PanicEngine {
     fn get_accumulated_flush_count_cf(cf: &str) -> Result<u64> {
         panic!()
     }
+
+    type DiskEngine = PanicEngine;
+    fn get_disk_engine(&self) -> &Self::DiskEngine {
+        panic!()
+    }
 }

components/engine_rocks/src/misc.rs

@@ -448,6 +448,11 @@ impl MiscExt for RocksEngine {
             .get();
         Ok(n)
     }
+
+    type DiskEngine = RocksEngine;
+    fn get_disk_engine(&self) -> &Self::DiskEngine {
+        self
+    }
 }
 
 #[cfg(test)]

components/engine_traits/src/misc.rs

@@ -178,4 +178,7 @@ pub trait MiscExt: CfNamesExt + FlowControlFactorsExt + WriteBatchExt {
         }
         Ok(n)
     }
+
+    type DiskEngine;
+    fn get_disk_engine(&self) -> &Self::DiskEngine;
 }

components/hybrid_engine/Cargo.toml

@@ -10,4 +10,5 @@ testexport = []
 [dependencies]
 engine_traits = { workspace = true }
 txn_types = { workspace = true }
-tikv_util = { workspace = true }
+tikv_util = { workspace = true }
+engine_rocks = { workspace = true }

components/hybrid_engine/src/engine.rs

@@ -42,6 +42,19 @@ where
     }
 }
 
+impl<EK, EC> HybridEngine<EK, EC>
+where
+    EK: KvEngine,
+    EC: RegionCacheEngine,
+{
+    pub fn new(disk_engine: EK, region_cache_engine: EC) -> Self {
+        Self {
+            disk_engine,
+            region_cache_engine,
+        }
+    }
+}
+
 // todo: implement KvEngine methods as well as it's super traits.
 impl<EK, EC> KvEngine for HybridEngine<EK, EC>
 where

components/hybrid_engine/src/lib.rs

@@ -22,3 +22,5 @@ mod sst;
 mod table_properties;
 mod ttl_properties;
 mod write_batch;
+
+pub use engine::HybridEngine;

components/hybrid_engine/src/misc.rs

@@ -124,4 +124,9 @@ where
     fn get_accumulated_flush_count_cf(cf: &str) -> Result<u64> {
         unimplemented!()
     }
+
+    type DiskEngine = EK::DiskEngine;
+    fn get_disk_engine(&self) -> &Self::DiskEngine {
+        self.disk_engine().get_disk_engine()
+    }
 }

components/raftstore/src/compacted_event_sender.rs

@@ -1,18 +1,26 @@
 // Copyright 2022 TiKV Project Authors. Licensed under Apache-2.0.
 use std::sync::Mutex;
 
-use engine_rocks::{CompactedEventSender, RocksCompactedEvent, RocksEngine};
-use engine_traits::RaftEngine;
+use engine_rocks::{CompactedEventSender, RocksCompactedEvent};
+use engine_traits::{KvEngine, RaftEngine};
 use tikv_util::error_unknown;
 
 use crate::store::{fsm::store::RaftRouter, StoreMsg};
 
 // raftstore v1's implementation
-pub struct RaftRouterCompactedEventSender<ER: RaftEngine> {
-    pub router: Mutex<RaftRouter<RocksEngine, ER>>,
+pub struct RaftRouterCompactedEventSender<EK, ER>
+where
+    EK: KvEngine,
+    ER: RaftEngine,
+{
+    pub router: Mutex<RaftRouter<EK, ER>>,
 }
 
-impl<ER: RaftEngine> CompactedEventSender for RaftRouterCompactedEventSender<ER> {
+impl<EK, ER> CompactedEventSender for RaftRouterCompactedEventSender<EK, ER>
+where
+    EK: KvEngine<CompactedEvent = RocksCompactedEvent>,
+    ER: RaftEngine,
+{
     fn send(&self, event: RocksCompactedEvent) {
         let router = self.router.lock().unwrap();
         let event = StoreMsg::CompactedEvent(event);

components/region_cache_memory_engine/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "region_cache_memory_engine"
+version = "0.0.1"
+edition = "2021"
+publish = false
+
+[features]
+testexport = []
+
+[dependencies]
+engine_traits = { workspace = true }
+collections = { workspace = true }
+skiplist-rs = { git = "https://github.com/tikv/skiplist-rs.git", branch = "main" }