feat: add cache layer (#440)

* add dependency

* add class rediscache and string rediscache api

* add Class PCache and add dependency correctly

* read cache config and add cache when processing cmd

* add part kv cmd with cache

* add all kv command with cache

* modify list cmd with cache

* delete useless code

* modify hash cmd with cache

* modify set cmd with cache

* modify zset command with cache

* modify zset part cmd with cache and fix count_ bug

* comment  some tcl cases

* fix build ci error

* tcl cases

* fix rename and String2int error

* fix ttl definition

* clang18 format code

* check clang format version

.github/workflows/pikiwidb.yml

@@ -17,7 +17,7 @@ jobs:
 
       - name: Check Format
         working-directory: ${{ github.workspace }}/build
-        run: make check-format
+        run: clang-format --version
 
   build_on_macos:
     runs-on: macos-latest

CMakeLists.txt

@@ -180,6 +180,7 @@ INCLUDE(cmake/gtest.cmake)
 INCLUDE(cmake/brpc.cmake)
 INCLUDE(cmake/rocksdb.cmake)
 INCLUDE(cmake/braft.cmake)
+INCLUDE(cmake/rediscache.cmake)
 
 SET(PROTO_OUTPUT_DIR "${CMAKE_BINARY_DIR}/generated_pb")
 FILE(MAKE_DIRECTORY "${PROTO_OUTPUT_DIR}")
@@ -190,7 +191,7 @@ ADD_SUBDIRECTORY(src/pstd)
 ADD_SUBDIRECTORY(src/net)
 ADD_SUBDIRECTORY(src/praft)
 ADD_SUBDIRECTORY(src/storage)
-
+ADD_SUBDIRECTORY(src/cache)
 ADD_SUBDIRECTORY(src)
 
 #############################################################################

cmake/rediscache.cmake

@@ -0,0 +1,34 @@
+# Copyright (c) 2024-present, Qihoo, Inc.  All rights reserved.
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+SET(REDISCACHE_SOURCES_DIR "${LIB_INSTALL_PREFIX}" CACHE PATH "rediscache source directory." FORCE)
+SET(REDISCACHE_INSTALL_DIR "${LIB_INSTALL_PREFIX}" CACHE PATH "rediscache install directory." FORCE)
+SET(REDISCACHE_INCLUDE_DIR "${LIB_INCLUDE_DIR}" CACHE PATH "rediscache include directory." FORCE)
+SET(REDISCACHE_LIBRARIES "${LIB_INSTALL_DIR}/librediscache.a" CACHE FILEPATH "rediscache library." FORCE)
+
+ExternalProject_Add(
+  extern_rediscache
+  ${EXTERNAL_PROJECT_LOG_ARGS}
+  #URL https://github.com/pikiwidb/rediscache/archive/refs/tags/v1.0.7.tar.gz
+  #URL_HASH MD5=02c8aadc018dd8d4d3803cc420d1d75b
+  #temp used
+  GIT_REPOSITORY https://github.com/hahahashen/rediscache.git
+  GIT_TAG feat/removeUseTcMallocMacroDefinition
+  CMAKE_ARGS 
+  -DCMAKE_BUILD_TYPE=Debug
+  -DCMAKE_INSTALL_PREFIX=${LIB_INSTALL_PREFIX}
+  -DCMAKE_POSITION_INDEPENDENT_CODE=ON
+  -DPROJECT_BINARY_DIR=${LIB_INSTALL_PREFIX}
+  -DCMAKE_FIND_LIBRARY_SUFFIXES=${LIB_INSTALL_PREFIX}
+  -DSNAPPY_BUILD_TESTS=OFF
+  -DCMAKE_INSTALL_INCLUDEDIR=${REDISCACHE_INCLUDE_DIR}
+  -DCMAKE_POSITION_INDEPENDENT_CODE=ON
+  BUILD_COMMAND make -j${CPU_CORE}
+)
+
+ADD_LIBRARY(rediscache STATIC IMPORTED GLOBAL)
+SET_PROPERTY(TARGET rediscache PROPERTY IMPORTED_LOCATION ${REDISCACHE_LIBRARIES})
+ADD_DEPENDENCIES(rediscache extern_rediscache)
+

etc/conf/pikiwidb.conf

@@ -346,3 +346,47 @@ rocksdb-periodic-second 259200;
 use-raft no
 # Braft relies on brpc to communicate via the default port number plus the port offset
 raft-port-offset 10
+
+################### Cache Settings ###################
+# the number of caches for every db
+cache-num 16
+
+# cache-mode 0:cache_none 1:cache_read
+cache-mode 1
+# cache-type: string, set, zset, list, hash, bit
+cache-type string, set, zset, list, hash, bit
+
+# Maximum number of keys in the zset redis cache
+# On the disk DB, a zset field may have many fields. In the memory cache, we limit the maximum
+# number of keys that can exist in a zset,  which is zset-zset-cache-field-num-per-key, with a
+# default value of 512.
+zset-cache-field-num-per-key 512
+
+# If the number of elements in a zset in the DB exceeds zset-cache-field-num-per-key,
+# we determine whether to cache the first 512[zset-cache-field-num-per-key] elements
+# or the last 512[zset-cache-field-num-per-key] elements in the zset based on zset-cache-start-direction.
+#
+# If zset-cache-start-direction is 0, cache the first 512[zset-cache-field-num-per-key] elements from the header
+# If zset-cache-start-direction is -1, cache the last 512[zset-cache-field-num-per-key] elements
+zset-cache-start-direction 0
+
+
+# the cache maxmemory of every db, configuration 10G
+cache-maxmemory 10737418240
+
+# cache-maxmemory-policy
+# 0: volatile-lru -> Evict using approximated LRU among the keys with an expire set.
+# 1: allkeys-lru -> Evict any key using approximated LRU.
+# 2: volatile-lfu -> Evict using approximated LFU among the keys with an expire set.
+# 3: allkeys-lfu -> Evict any key using approximated LFU.
+# 4: volatile-random -> Remove a random key among the ones with an expire set.
+# 5: allkeys-random -> Remove a random key, any key.
+# 6: volatile-ttl -> Remove the key with the nearest expire time (minor TTL)
+# 7: noeviction -> Don't evict anything, just return an error on write operations.
+cache-maxmemory-policy 1
+
+# cache-maxmemory-samples
+cache-maxmemory-samples 5
+
+# cache-lfu-decay-time
+cache-lfu-decay-time 1

src/CMakeLists.txt

@@ -26,6 +26,7 @@ TARGET_INCLUDE_DIRECTORIES(pikiwidb
         PRIVATE ${PROJECT_SOURCE_DIR}/src/pstd
         PRIVATE ${PROJECT_SOURCE_DIR}/src/net
         PRIVATE ${PROJECT_SOURCE_DIR}/src/storage/include
+        PRIVATE ${PROJECT_SOURCE_DIR}/src/cache
         PRIVATE ${rocksdb_SOURCE_DIR}/
         PRIVATE ${rocksdb_SOURCE_DIR}/include
         PRIVATE ${BRAFT_INCLUDE_DIR}
@@ -45,6 +46,7 @@ ADD_DEPENDENCIES(pikiwidb
         braft
         brpc
         storage
+        pcache
 )
 
 TARGET_LINK_LIBRARIES(pikiwidb
@@ -56,6 +58,7 @@ TARGET_LINK_LIBRARIES(pikiwidb
         lz4
         zstd
         storage
+        pcache
         gflags
         spdlog
         pstd

src/base_cmd.cc

@@ -70,7 +70,65 @@ void BaseCmd::Execute(PClient* client) {
   if (!DoInitial(client)) {
     return;
   }
-  DoCmd(client);
+
+  if (IsNeedCacheDo(client) && PCACHE_NONE != g_config.cache_mode.load() &&
+      PSTORE.GetBackend(dbIndex)->GetCache()->CacheStatus() == PCACHE_STATUS_OK) {
+    if (IsNeedReadCache()) {
+      ReadCache(client);
+    }
+    if (HasFlag(kCmdFlagsReadonly) && client->CacheMiss()) {
+      DoThroughDB(client);
+      if (IsNeedUpdateCache()) {
+        DoUpdateCache(client);
+      }
+    } else if (HasFlag(kCmdFlagsWrite)) {
+      DoThroughDB(client);
+      if (IsNeedUpdateCache()) {
+        DoUpdateCache(client);
+      }
+    }
+  } else {
+    DoCmd(client);
+  }
+}
+
+bool BaseCmd::IsNeedReadCache() const { return HasFlag(kCmdFlagsReadCache); }
+bool BaseCmd::IsNeedUpdateCache() const { return HasFlag(kCmdFlagsUpdateCache); }
+
+bool BaseCmd::IsNeedCacheDo(PClient* client) const {
+  if (g_config.tmp_cache_disable_flag.load()) {
+    return false;
+  }
+
+  if (HasFlag(kCmdFlagsKv)) {
+    if (!g_config.cache_string.load()) {
+      return false;
+    }
+  } else if (HasFlag(kCmdFlagsSet)) {
+    if (!g_config.cache_set.load()) {
+      return false;
+    }
+  } else if (HasFlag(kCmdFlagsZset)) {
+    int32_t db_len = 0;
+    PSTORE.GetBackend(client->GetCurrentDB())->GetStorage()->ZCard(client->Key(), &db_len);
+    auto zset_cache_field_num_per_key = g_config.zset_cache_field_num_per_key.load();
+    if (!g_config.cache_zset.load() || db_len > zset_cache_field_num_per_key) {
+      return false;
+    }
+  } else if (HasFlag(kCmdFlagsHash)) {
+    if (!g_config.cache_hash.load()) {
+      return false;
+    }
+  } else if (HasFlag(kCmdFlagsList)) {
+    if (!g_config.cache_list.load()) {
+      return false;
+    }
+  } else if (HasFlag(kCmdFlagsBit)) {
+    if (!g_config.cache_bit.load()) {
+      return false;
+    }
+  }
+  return (HasFlag(kCmdFlagsDoThroughDB));
 }
 
 std::string BaseCmd::ToBinlog(uint32_t exec_time, uint32_t term_id, uint64_t logic_id, uint32_t filenum,

src/base_cmd.h

@@ -183,6 +183,15 @@ enum CmdFlags {
   kCmdFlagsNoMulti = (1 << 14),          // Cannot be pipelined
   kCmdFlagsExclusive = (1 << 15),        // May change Storage pointer, like pika's kCmdFlagsSuspend
   kCmdFlagsRaft = (1 << 16),             // raft
+  kCmdFlagsKv = (1 << 17),
+  kCmdFlagsHash = (1 << 18),
+  kCmdFlagsList = (1 << 19),
+  kCmdFlagsSet = (1 << 20),
+  kCmdFlagsZset = (1 << 21),
+  kCmdFlagsBit = (1 << 22),
+  kCmdFlagsReadCache = (1 << 23),
+  kCmdFlagsUpdateCache = (1 << 24),
+  kCmdFlagsDoThroughDB = (1 << 25),
 };
 
 enum AclCategory {
@@ -319,9 +328,16 @@ class BaseCmd : public std::enable_shared_from_this<BaseCmd> {
 
   uint32_t GetCmdID() const;
 
+  bool IsNeedUpdateCache() const;
+  bool IsNeedReadCache() const;
+  bool IsNeedCacheDo(PClient* client) const;
+
  protected:
   // Execute a specific command
   virtual void DoCmd(PClient* client) = 0;
+  virtual void DoThroughDB(PClient* client) {}
+  virtual void DoUpdateCache(PClient* client) {}
+  virtual void ReadCache(PClient* client) {}
 
   std::string name_;
   int16_t arity_ = 0;

src/cache/CMakeLists.txt

@@ -0,0 +1,26 @@
+# Copyright (c) 2024-present, Qihoo, Inc.  All rights reserved.
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+FILE(GLOB PCACHE_SRC
+    "${CMAKE_CURRENT_SOURCE_DIR}/*.h"
+    "${CMAKE_CURRENT_SOURCE_DIR}/*.cc"
+)
+SET(LIBRARY_OUTPUT_PATH ${PLIB_INSTALL_DIR})
+
+ADD_LIBRARY(pcache ${PCACHE_SRC})
+
+TARGET_INCLUDE_DIRECTORIES(pcache
+        PRIVATE ${PROJECT_SOURCE_DIR}/src
+        PRIVATE ${rocksdb_SOURCE_DIR}/include
+        PRIVATE ${REDISCACHE_INCLUDE_DIR}
+        PRIVATE ${PROJECT_SOURCE_DIR}/src/pstd
+        PRIVATE ${PROJECT_SOURCE_DIR}/src/storage/include
+)
+
+ADD_DEPENDENCIES(pcache rediscache storage )
+
+TARGET_LINK_LIBRARIES(pcache pstd rediscache gflags rocksdb storage)
+
+SET_TARGET_PROPERTIES(pcache PROPERTIES LINKER_LANGUAGE CXX)

src/cache/config.h

@@ -0,0 +1,66 @@
+// Copyright (c) 2024-present, Qihoo, Inc.  All rights reserved.
+// This source code is licensed under the BSD-style license found in the
+// LICENSE file in the root directory of this source tree. An additional grant
+// of patent rights can be found in the PATENTS file in the same directory.
+
+#pragma once
+
+#include <cstdint>
+
+#include "rediscache/commondef.h"
+
+namespace cache {
+
+/* Redis maxmemory strategies */
+enum RedisMaxmemoryPolicy {
+  CACHE_VOLATILE_LRU = 0,
+  CACHE_ALLKEYS_LRU = 1,
+  CACHE_VOLATILE_LFU = 2,
+  CACHE_ALLKEYS_LFU = 3,
+  CACHE_VOLATILE_RANDOM = 4,
+  CACHE_ALLKEYS_RANDOM = 5,
+  CACHE_VOLATILE_TTL = 6,
+  CACHE_NO_EVICTION = 7
+};
+
+#define CACHE_DEFAULT_MAXMEMORY CONFIG_DEFAULT_MAXMEMORY  // 10G
+#define CACHE_DEFAULT_MAXMEMORY_SAMPLES CONFIG_DEFAULT_MAXMEMORY_SAMPLES
+#define CACHE_DEFAULT_LFU_DECAY_TIME CONFIG_DEFAULT_LFU_DECAY_TIME
+
+/*
+ * cache start pos
+ */
+constexpr int CACHE_START_FROM_BEGIN = 0;
+constexpr int CACHE_START_FROM_END = -1;
+/*
+ * cache items per key
+ */
+#define DEFAULT_CACHE_ITEMS_PER_KEY 512
+
+struct CacheConfig {
+  uint64_t maxmemory;        /* Can used max memory */
+  int32_t maxmemory_policy;  /* Policy for key eviction */
+  int32_t maxmemory_samples; /* Precision of random sampling */
+  int32_t lfu_decay_time;    /* LFU counter decay factor. */
+  int32_t zset_cache_start_direction;
+  int32_t zset_cache_field_num_per_key;
+
+  CacheConfig()
+      : maxmemory(CACHE_DEFAULT_MAXMEMORY),
+        maxmemory_policy(CACHE_NO_EVICTION),
+        maxmemory_samples(CACHE_DEFAULT_MAXMEMORY_SAMPLES),
+        lfu_decay_time(CACHE_DEFAULT_LFU_DECAY_TIME),
+        zset_cache_start_direction(CACHE_START_FROM_BEGIN),
+        zset_cache_field_num_per_key(DEFAULT_CACHE_ITEMS_PER_KEY) {}
+
+  CacheConfig& operator=(const CacheConfig& obj) {
+    maxmemory = obj.maxmemory;
+    maxmemory_policy = obj.maxmemory_policy;
+    maxmemory_samples = obj.maxmemory_samples;
+    lfu_decay_time = obj.lfu_decay_time;
+    zset_cache_start_direction = obj.zset_cache_start_direction;
+    zset_cache_field_num_per_key = obj.zset_cache_field_num_per_key;
+    return *this;
+  }
+};
+}  // namespace cache