rocksdb/cache/lru_cache_test.cc
anand76 add68bd28a Add a stat to count secondary cache hits (#8666)
Summary:
Add a stat for secondary cache hits. The ```Cache::Lookup``` API had an unused ```stats``` parameter. This PR uses that to pass the pointer to a ```Statistics``` object that ```LRUCache``` uses to record the stat.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8666

Test Plan: Update a unit test in lru_cache_test

Reviewed By: zhichao-cao

Differential Revision: D30353816

Pulled By: anand1976

fbshipit-source-id: 2046f78b460428877a26ffdd2bb914ae47dfbe77
2021-08-16 21:01:14 -07:00

1188 lines
43 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "cache/lru_cache.h"
#include <string>
#include <vector>
#include "db/db_test_util.h"
#include "file/sst_file_manager_impl.h"
#include "port/port.h"
#include "port/stack_trace.h"
#include "rocksdb/cache.h"
#include "rocksdb/io_status.h"
#include "rocksdb/sst_file_manager.h"
#include "test_util/testharness.h"
#include "util/coding.h"
#include "util/random.h"
#include "utilities/fault_injection_fs.h"
namespace ROCKSDB_NAMESPACE {
class LRUCacheTest : public testing::Test {
public:
LRUCacheTest() {}
~LRUCacheTest() override { DeleteCache(); }
void DeleteCache() {
if (cache_ != nullptr) {
cache_->~LRUCacheShard();
port::cacheline_aligned_free(cache_);
cache_ = nullptr;
}
}
void NewCache(size_t capacity, double high_pri_pool_ratio = 0.0,
bool use_adaptive_mutex = kDefaultToAdaptiveMutex) {
DeleteCache();
cache_ = reinterpret_cast<LRUCacheShard*>(
port::cacheline_aligned_alloc(sizeof(LRUCacheShard)));
new (cache_) LRUCacheShard(
capacity, false /*strict_capcity_limit*/, high_pri_pool_ratio,
use_adaptive_mutex, kDontChargeCacheMetadata,
24 /*max_upper_hash_bits*/, nullptr /*secondary_cache*/);
}
void Insert(const std::string& key,
Cache::Priority priority = Cache::Priority::LOW) {
EXPECT_OK(cache_->Insert(key, 0 /*hash*/, nullptr /*value*/, 1 /*charge*/,
nullptr /*deleter*/, nullptr /*handle*/,
priority));
}
void Insert(char key, Cache::Priority priority = Cache::Priority::LOW) {
Insert(std::string(1, key), priority);
}
bool Lookup(const std::string& key) {
auto handle = cache_->Lookup(key, 0 /*hash*/);
if (handle) {
cache_->Release(handle);
return true;
}
return false;
}
bool Lookup(char key) { return Lookup(std::string(1, key)); }
void Erase(const std::string& key) { cache_->Erase(key, 0 /*hash*/); }
void ValidateLRUList(std::vector<std::string> keys,
size_t num_high_pri_pool_keys = 0) {
LRUHandle* lru;
LRUHandle* lru_low_pri;
cache_->TEST_GetLRUList(&lru, &lru_low_pri);
LRUHandle* iter = lru;
bool in_high_pri_pool = false;
size_t high_pri_pool_keys = 0;
if (iter == lru_low_pri) {
in_high_pri_pool = true;
}
for (const auto& key : keys) {
iter = iter->next;
ASSERT_NE(lru, iter);
ASSERT_EQ(key, iter->key().ToString());
ASSERT_EQ(in_high_pri_pool, iter->InHighPriPool());
if (in_high_pri_pool) {
high_pri_pool_keys++;
}
if (iter == lru_low_pri) {
ASSERT_FALSE(in_high_pri_pool);
in_high_pri_pool = true;
}
}
ASSERT_EQ(lru, iter->next);
ASSERT_TRUE(in_high_pri_pool);
ASSERT_EQ(num_high_pri_pool_keys, high_pri_pool_keys);
}
private:
LRUCacheShard* cache_ = nullptr;
};
TEST_F(LRUCacheTest, BasicLRU) {
NewCache(5);
for (char ch = 'a'; ch <= 'e'; ch++) {
Insert(ch);
}
ValidateLRUList({"a", "b", "c", "d", "e"});
for (char ch = 'x'; ch <= 'z'; ch++) {
Insert(ch);
}
ValidateLRUList({"d", "e", "x", "y", "z"});
ASSERT_FALSE(Lookup("b"));
ValidateLRUList({"d", "e", "x", "y", "z"});
ASSERT_TRUE(Lookup("e"));
ValidateLRUList({"d", "x", "y", "z", "e"});
ASSERT_TRUE(Lookup("z"));
ValidateLRUList({"d", "x", "y", "e", "z"});
Erase("x");
ValidateLRUList({"d", "y", "e", "z"});
ASSERT_TRUE(Lookup("d"));
ValidateLRUList({"y", "e", "z", "d"});
Insert("u");
ValidateLRUList({"y", "e", "z", "d", "u"});
Insert("v");
ValidateLRUList({"e", "z", "d", "u", "v"});
}
TEST_F(LRUCacheTest, MidpointInsertion) {
// Allocate 2 cache entries to high-pri pool.
NewCache(5, 0.45);
Insert("a", Cache::Priority::LOW);
Insert("b", Cache::Priority::LOW);
Insert("c", Cache::Priority::LOW);
Insert("x", Cache::Priority::HIGH);
Insert("y", Cache::Priority::HIGH);
ValidateLRUList({"a", "b", "c", "x", "y"}, 2);
// Low-pri entries inserted to the tail of low-pri list (the midpoint).
// After lookup, it will move to the tail of the full list.
Insert("d", Cache::Priority::LOW);
ValidateLRUList({"b", "c", "d", "x", "y"}, 2);
ASSERT_TRUE(Lookup("d"));
ValidateLRUList({"b", "c", "x", "y", "d"}, 2);
// High-pri entries will be inserted to the tail of full list.
Insert("z", Cache::Priority::HIGH);
ValidateLRUList({"c", "x", "y", "d", "z"}, 2);
}
TEST_F(LRUCacheTest, EntriesWithPriority) {
// Allocate 2 cache entries to high-pri pool.
NewCache(5, 0.45);
Insert("a", Cache::Priority::LOW);
Insert("b", Cache::Priority::LOW);
Insert("c", Cache::Priority::LOW);
ValidateLRUList({"a", "b", "c"}, 0);
// Low-pri entries can take high-pri pool capacity if available
Insert("u", Cache::Priority::LOW);
Insert("v", Cache::Priority::LOW);
ValidateLRUList({"a", "b", "c", "u", "v"}, 0);
Insert("X", Cache::Priority::HIGH);
Insert("Y", Cache::Priority::HIGH);
ValidateLRUList({"c", "u", "v", "X", "Y"}, 2);
// High-pri entries can overflow to low-pri pool.
Insert("Z", Cache::Priority::HIGH);
ValidateLRUList({"u", "v", "X", "Y", "Z"}, 2);
// Low-pri entries will be inserted to head of low-pri pool.
Insert("a", Cache::Priority::LOW);
ValidateLRUList({"v", "X", "a", "Y", "Z"}, 2);
// Low-pri entries will be inserted to head of high-pri pool after lookup.
ASSERT_TRUE(Lookup("v"));
ValidateLRUList({"X", "a", "Y", "Z", "v"}, 2);
// High-pri entries will be inserted to the head of the list after lookup.
ASSERT_TRUE(Lookup("X"));
ValidateLRUList({"a", "Y", "Z", "v", "X"}, 2);
ASSERT_TRUE(Lookup("Z"));
ValidateLRUList({"a", "Y", "v", "X", "Z"}, 2);
Erase("Y");
ValidateLRUList({"a", "v", "X", "Z"}, 2);
Erase("X");
ValidateLRUList({"a", "v", "Z"}, 1);
Insert("d", Cache::Priority::LOW);
Insert("e", Cache::Priority::LOW);
ValidateLRUList({"a", "v", "d", "e", "Z"}, 1);
Insert("f", Cache::Priority::LOW);
Insert("g", Cache::Priority::LOW);
ValidateLRUList({"d", "e", "f", "g", "Z"}, 1);
ASSERT_TRUE(Lookup("d"));
ValidateLRUList({"e", "f", "g", "Z", "d"}, 2);
}
class TestSecondaryCache : public SecondaryCache {
public:
// Specifies what action to take on a lookup for a particular key
enum ResultType {
SUCCESS,
// Fail lookup immediately
FAIL,
// Defer the result. It will returned after Wait/WaitAll is called
DEFER,
// Defer the result and eventually return failure
DEFER_AND_FAIL
};
using ResultMap = std::unordered_map<std::string, ResultType>;
explicit TestSecondaryCache(size_t capacity)
: num_inserts_(0), num_lookups_(0), inject_failure_(false) {
cache_ = NewLRUCache(capacity, 0, false, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
}
~TestSecondaryCache() override { cache_.reset(); }
const char* Name() const override { return "TestSecondaryCache"; }
void InjectFailure() { inject_failure_ = true; }
void ResetInjectFailure() { inject_failure_ = false; }
void SetDbSessionId(const std::string& db_session_id) {
db_session_id_ = db_session_id;
}
Status Insert(const Slice& key, void* value,
const Cache::CacheItemHelper* helper) override {
if (inject_failure_) {
return Status::Corruption("Insertion Data Corrupted");
}
assert(IsDbSessionIdAsKeyPrefix(key) == true);
size_t size;
char* buf;
Status s;
num_inserts_++;
size = (*helper->size_cb)(value);
buf = new char[size + sizeof(uint64_t)];
EncodeFixed64(buf, size);
s = (*helper->saveto_cb)(value, 0, size, buf + sizeof(uint64_t));
if (!s.ok()) {
delete[] buf;
return s;
}
return cache_->Insert(key, buf, size,
[](const Slice& /*key*/, void* val) -> void {
delete[] static_cast<char*>(val);
});
}
std::unique_ptr<SecondaryCacheResultHandle> Lookup(
const Slice& key, const Cache::CreateCallback& create_cb,
bool /*wait*/) override {
std::string key_str = key.ToString();
TEST_SYNC_POINT_CALLBACK("TestSecondaryCache::Lookup", &key_str);
std::unique_ptr<SecondaryCacheResultHandle> secondary_handle;
ResultType type = ResultType::SUCCESS;
auto iter = result_map_.find(key.ToString());
if (iter != result_map_.end()) {
type = iter->second;
}
if (type == ResultType::FAIL) {
return secondary_handle;
}
Cache::Handle* handle = cache_->Lookup(key);
num_lookups_++;
if (handle) {
void* value = nullptr;
size_t charge = 0;
Status s;
if (type != ResultType::DEFER_AND_FAIL) {
char* ptr = (char*)cache_->Value(handle);
size_t size = DecodeFixed64(ptr);
ptr += sizeof(uint64_t);
s = create_cb(ptr, size, &value, &charge);
}
if (s.ok()) {
secondary_handle.reset(new TestSecondaryCacheResultHandle(
cache_.get(), handle, value, charge, type));
} else {
cache_->Release(handle);
}
}
return secondary_handle;
}
void Erase(const Slice& /*key*/) override {}
void WaitAll(std::vector<SecondaryCacheResultHandle*> handles) override {
for (SecondaryCacheResultHandle* handle : handles) {
TestSecondaryCacheResultHandle* sec_handle =
static_cast<TestSecondaryCacheResultHandle*>(handle);
sec_handle->SetReady();
}
}
std::string GetPrintableOptions() const override { return ""; }
void SetResultMap(ResultMap&& map) { result_map_ = std::move(map); }
uint32_t num_inserts() { return num_inserts_; }
uint32_t num_lookups() { return num_lookups_; }
bool IsDbSessionIdAsKeyPrefix(const Slice& key) {
if (db_session_id_.size() == 0) {
return true;
}
if (key.size() < 20) {
return false;
}
std::string s_key = key.ToString();
if (s_key.substr(0, 20) != db_session_id_) {
return false;
}
return true;
}
private:
class TestSecondaryCacheResultHandle : public SecondaryCacheResultHandle {
public:
TestSecondaryCacheResultHandle(Cache* cache, Cache::Handle* handle,
void* value, size_t size, ResultType type)
: cache_(cache),
handle_(handle),
value_(value),
size_(size),
is_ready_(true) {
if (type != ResultType::SUCCESS) {
is_ready_ = false;
}
}
~TestSecondaryCacheResultHandle() override { cache_->Release(handle_); }
bool IsReady() override { return is_ready_; }
void Wait() override {}
void* Value() override {
assert(is_ready_);
return value_;
}
size_t Size() override { return Value() ? size_ : 0; }
void SetReady() { is_ready_ = true; }
private:
Cache* cache_;
Cache::Handle* handle_;
void* value_;
size_t size_;
bool is_ready_;
};
std::shared_ptr<Cache> cache_;
uint32_t num_inserts_;
uint32_t num_lookups_;
bool inject_failure_;
std::string db_session_id_;
ResultMap result_map_;
};
class DBSecondaryCacheTest : public DBTestBase {
public:
DBSecondaryCacheTest()
: DBTestBase("db_secondary_cache_test", /*env_do_fsync=*/true) {
fault_fs_.reset(new FaultInjectionTestFS(env_->GetFileSystem()));
fault_env_.reset(new CompositeEnvWrapper(env_, fault_fs_));
}
std::shared_ptr<FaultInjectionTestFS> fault_fs_;
std::unique_ptr<Env> fault_env_;
};
class LRUSecondaryCacheTest : public LRUCacheTest {
public:
LRUSecondaryCacheTest() : fail_create_(false) {}
~LRUSecondaryCacheTest() {}
protected:
class TestItem {
public:
TestItem(const char* buf, size_t size) : buf_(new char[size]), size_(size) {
memcpy(buf_.get(), buf, size);
}
~TestItem() {}
char* Buf() { return buf_.get(); }
size_t Size() { return size_; }
std::string ToString() { return std::string(Buf(), Size()); }
private:
std::unique_ptr<char[]> buf_;
size_t size_;
};
static size_t SizeCallback(void* obj) {
return reinterpret_cast<TestItem*>(obj)->Size();
}
static Status SaveToCallback(void* from_obj, size_t from_offset,
size_t length, void* out) {
TestItem* item = reinterpret_cast<TestItem*>(from_obj);
char* buf = item->Buf();
EXPECT_EQ(length, item->Size());
EXPECT_EQ(from_offset, 0);
memcpy(out, buf, length);
return Status::OK();
}
static void DeletionCallback(const Slice& /*key*/, void* obj) {
delete reinterpret_cast<TestItem*>(obj);
}
static Cache::CacheItemHelper helper_;
static Status SaveToCallbackFail(void* /*obj*/, size_t /*offset*/,
size_t /*size*/, void* /*out*/) {
return Status::NotSupported();
}
static Cache::CacheItemHelper helper_fail_;
Cache::CreateCallback test_item_creator =
[&](void* buf, size_t size, void** out_obj, size_t* charge) -> Status {
if (fail_create_) {
return Status::NotSupported();
}
*out_obj = reinterpret_cast<void*>(new TestItem((char*)buf, size));
*charge = size;
return Status::OK();
};
void SetFailCreate(bool fail) { fail_create_ = fail; }
private:
bool fail_create_;
};
Cache::CacheItemHelper LRUSecondaryCacheTest::helper_(
LRUSecondaryCacheTest::SizeCallback, LRUSecondaryCacheTest::SaveToCallback,
LRUSecondaryCacheTest::DeletionCallback);
Cache::CacheItemHelper LRUSecondaryCacheTest::helper_fail_(
LRUSecondaryCacheTest::SizeCallback,
LRUSecondaryCacheTest::SaveToCallbackFail,
LRUSecondaryCacheTest::DeletionCallback);
TEST_F(LRUSecondaryCacheTest, BasicTest) {
LRUCacheOptions opts(1024, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(2048);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
std::shared_ptr<Statistics> stats = CreateDBStatistics();
Random rnd(301);
std::string str1 = rnd.RandomString(1020);
TestItem* item1 = new TestItem(str1.data(), str1.length());
ASSERT_OK(cache->Insert("k1", item1, &LRUSecondaryCacheTest::helper_,
str1.length()));
std::string str2 = rnd.RandomString(1020);
TestItem* item2 = new TestItem(str2.data(), str2.length());
// k1 should be demoted to NVM
ASSERT_OK(cache->Insert("k2", item2, &LRUSecondaryCacheTest::helper_,
str2.length()));
Cache::Handle* handle;
handle =
cache->Lookup("k2", &LRUSecondaryCacheTest::helper_, test_item_creator,
Cache::Priority::LOW, true, stats.get());
ASSERT_NE(handle, nullptr);
cache->Release(handle);
// This lookup should promote k1 and demote k2
handle =
cache->Lookup("k1", &LRUSecondaryCacheTest::helper_, test_item_creator,
Cache::Priority::LOW, true, stats.get());
ASSERT_NE(handle, nullptr);
cache->Release(handle);
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 1u);
ASSERT_EQ(stats->getTickerCount(SECONDARY_CACHE_HITS),
secondary_cache->num_lookups());
cache.reset();
secondary_cache.reset();
}
TEST_F(LRUSecondaryCacheTest, BasicFailTest) {
LRUCacheOptions opts(1024, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(2048);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
Random rnd(301);
std::string str1 = rnd.RandomString(1020);
TestItem* item1 = new TestItem(str1.data(), str1.length());
ASSERT_NOK(cache->Insert("k1", item1, nullptr, str1.length()));
ASSERT_OK(cache->Insert("k1", item1, &LRUSecondaryCacheTest::helper_,
str1.length()));
Cache::Handle* handle;
handle = cache->Lookup("k2", nullptr, test_item_creator, Cache::Priority::LOW,
true);
ASSERT_EQ(handle, nullptr);
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, false);
ASSERT_EQ(handle, nullptr);
cache.reset();
secondary_cache.reset();
}
TEST_F(LRUSecondaryCacheTest, SaveFailTest) {
LRUCacheOptions opts(1024, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(2048);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
Random rnd(301);
std::string str1 = rnd.RandomString(1020);
TestItem* item1 = new TestItem(str1.data(), str1.length());
ASSERT_OK(cache->Insert("k1", item1, &LRUSecondaryCacheTest::helper_fail_,
str1.length()));
std::string str2 = rnd.RandomString(1020);
TestItem* item2 = new TestItem(str2.data(), str2.length());
// k1 should be demoted to NVM
ASSERT_OK(cache->Insert("k2", item2, &LRUSecondaryCacheTest::helper_fail_,
str2.length()));
Cache::Handle* handle;
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_fail_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
cache->Release(handle);
// This lookup should fail, since k1 demotion would have failed
handle = cache->Lookup("k1", &LRUSecondaryCacheTest::helper_fail_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_EQ(handle, nullptr);
// Since k1 didn't get promoted, k2 should still be in cache
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_fail_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
cache->Release(handle);
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 1u);
cache.reset();
secondary_cache.reset();
}
TEST_F(LRUSecondaryCacheTest, CreateFailTest) {
LRUCacheOptions opts(1024, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(2048);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
Random rnd(301);
std::string str1 = rnd.RandomString(1020);
TestItem* item1 = new TestItem(str1.data(), str1.length());
ASSERT_OK(cache->Insert("k1", item1, &LRUSecondaryCacheTest::helper_,
str1.length()));
std::string str2 = rnd.RandomString(1020);
TestItem* item2 = new TestItem(str2.data(), str2.length());
// k1 should be demoted to NVM
ASSERT_OK(cache->Insert("k2", item2, &LRUSecondaryCacheTest::helper_,
str2.length()));
Cache::Handle* handle;
SetFailCreate(true);
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
cache->Release(handle);
// This lookup should fail, since k1 creation would have failed
handle = cache->Lookup("k1", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_EQ(handle, nullptr);
// Since k1 didn't get promoted, k2 should still be in cache
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
cache->Release(handle);
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 1u);
cache.reset();
secondary_cache.reset();
}
TEST_F(LRUSecondaryCacheTest, FullCapacityTest) {
LRUCacheOptions opts(1024, 0, /*_strict_capacity_limit=*/true, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(2048);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
Random rnd(301);
std::string str1 = rnd.RandomString(1020);
TestItem* item1 = new TestItem(str1.data(), str1.length());
ASSERT_OK(cache->Insert("k1", item1, &LRUSecondaryCacheTest::helper_,
str1.length()));
std::string str2 = rnd.RandomString(1020);
TestItem* item2 = new TestItem(str2.data(), str2.length());
// k1 should be demoted to NVM
ASSERT_OK(cache->Insert("k2", item2, &LRUSecondaryCacheTest::helper_,
str2.length()));
Cache::Handle* handle;
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
// k1 promotion should fail due to the block cache being at capacity,
// but the lookup should still succeed
Cache::Handle* handle2;
handle2 = cache->Lookup("k1", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle2, nullptr);
// Since k1 didn't get inserted, k2 should still be in cache
cache->Release(handle);
cache->Release(handle2);
handle = cache->Lookup("k2", &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, true);
ASSERT_NE(handle, nullptr);
cache->Release(handle);
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 1u);
cache.reset();
secondary_cache.reset();
}
// In this test, the block cache size is set to 4096, after insert 6 KV-pairs
// and flush, there are 5 blocks in this SST file, 2 data blocks and 3 meta
// blocks. block_1 size is 4096 and block_2 size is 2056. The total size
// of the meta blocks are about 900 to 1000. Therefore, in any situation,
// if we try to insert block_1 to the block cache, it will always fails. Only
// block_2 will be successfully inserted into the block cache.
TEST_F(DBSecondaryCacheTest, TestSecondaryCacheCorrectness1) {
LRUCacheOptions opts(4 * 1024, 0, false, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.env = fault_env_.get();
fault_fs_->SetFailGetUniqueId(true);
// Set the file paranoid check, so after flush, the file will be read
// all the blocks will be accessed.
options.paranoid_file_checks = true;
DestroyAndReopen(options);
std::string session_id;
ASSERT_OK(db_->GetDbSessionId(session_id));
secondary_cache->SetDbSessionId(session_id);
Random rnd(301);
const int N = 6;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(1007);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
// After Flush is successful, RocksDB do the paranoid check for the new
// SST file. Meta blocks are always cached in the block cache and they
// will not be evicted. When block_2 is cache miss and read out, it is
// inserted to the block cache. Note that, block_1 is never successfully
// inserted to the block cache. Here are 2 lookups in the secondary cache
// for block_1 and block_2
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
Compact("a", "z");
// Compaction will create the iterator to scan the whole file. So all the
// blocks are needed. Meta blocks are always cached. When block_1 is read
// out, block_2 is evicted from block cache and inserted to secondary
// cache.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 3u);
std::string v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// The first data block is not in the cache, similarly, trigger the block
// cache Lookup and secondary cache lookup for block_1. But block_1 will not
// be inserted successfully due to the size. Currently, cache only has
// the meta blocks.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 4u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// The second data block is not in the cache, similarly, trigger the block
// cache Lookup and secondary cache lookup for block_2 and block_2 is found
// in the secondary cache. Now block cache has block_2
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// block_2 is in the block cache. There is a block cache hit. No need to
// lookup or insert the secondary cache.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// Lookup the first data block, not in the block cache, so lookup the
// secondary cache. Also not in the secondary cache. After Get, still
// block_1 is will not be cached.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 6u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// Lookup the first data block, not in the block cache, so lookup the
// secondary cache. Also not in the secondary cache. After Get, still
// block_1 is will not be cached.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 7u);
Destroy(options);
}
// In this test, the block cache size is set to 6100, after insert 6 KV-pairs
// and flush, there are 5 blocks in this SST file, 2 data blocks and 3 meta
// blocks. block_1 size is 4096 and block_2 size is 2056. The total size
// of the meta blocks are about 900 to 1000. Therefore, we can successfully
// insert and cache block_1 in the block cache (this is the different place
// from TestSecondaryCacheCorrectness1)
TEST_F(DBSecondaryCacheTest, TestSecondaryCacheCorrectness2) {
LRUCacheOptions opts(6100, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.paranoid_file_checks = true;
options.env = fault_env_.get();
fault_fs_->SetFailGetUniqueId(true);
DestroyAndReopen(options);
std::string session_id;
ASSERT_OK(db_->GetDbSessionId(session_id));
secondary_cache->SetDbSessionId(session_id);
Random rnd(301);
const int N = 6;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(1007);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
// After Flush is successful, RocksDB do the paranoid check for the new
// SST file. Meta blocks are always cached in the block cache and they
// will not be evicted. When block_2 is cache miss and read out, it is
// inserted to the block cache. Thefore, block_1 is evicted from block
// cache and successfully inserted to the secondary cache. Here are 2
// lookups in the secondary cache for block_1 and block_2.
ASSERT_EQ(secondary_cache->num_inserts(), 1u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
Compact("a", "z");
// Compaction will create the iterator to scan the whole file. So all the
// blocks are needed. After Flush, only block_2 is cached in block cache
// and block_1 is in the secondary cache. So when read block_1, it is
// read out from secondary cache and inserted to block cache. At the same
// time, block_2 is inserted to secondary cache. Now, secondary cache has
// both block_1 and block_2. After compaction, block_1 is in the cache.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 3u);
std::string v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// This Get needs to access block_1, since block_1 is cached in block cache
// there is no secondary cache lookup.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 3u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// This Get needs to access block_2 which is not in the block cache. So
// it will lookup the secondary cache for block_2 and cache it in the
// block_cache.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 4u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// This Get needs to access block_2 which is already in the block cache.
// No need to lookup secondary cache.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 4u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// This Get needs to access block_1, since block_1 is not in block cache
// there is one econdary cache lookup. Then, block_1 is cached in the
// block cache.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// This Get needs to access block_1, since block_1 is cached in block cache
// there is no secondary cache lookup.
ASSERT_EQ(secondary_cache->num_inserts(), 2u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
Destroy(options);
}
// The block cache size is set to 1024*1024, after insert 6 KV-pairs
// and flush, there are 5 blocks in this SST file, 2 data blocks and 3 meta
// blocks. block_1 size is 4096 and block_2 size is 2056. The total size
// of the meta blocks are about 900 to 1000. Therefore, we can successfully
// cache all the blocks in the block cache and there is not secondary cache
// insertion. 2 lookup is needed for the blocks.
TEST_F(DBSecondaryCacheTest, NoSecondaryCacheInsertion) {
LRUCacheOptions opts(1024 * 1024, 0, false, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.paranoid_file_checks = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.env = fault_env_.get();
fault_fs_->SetFailGetUniqueId(true);
DestroyAndReopen(options);
std::string session_id;
ASSERT_OK(db_->GetDbSessionId(session_id));
secondary_cache->SetDbSessionId(session_id);
Random rnd(301);
const int N = 6;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(1000);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
// After Flush is successful, RocksDB do the paranoid check for the new
// SST file. Meta blocks are always cached in the block cache and they
// will not be evicted. Now, block cache is large enough, it cache
// both block_1 and block_2. When first time read block_1 and block_2
// there are cache misses. So 2 secondary cache lookups are needed for
// the 2 blocks
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
Compact("a", "z");
// Compaction will iterate the whole SST file. Since all the data blocks
// are in the block cache. No need to lookup the secondary cache.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
std::string v = Get(Key(0));
ASSERT_EQ(1000, v.size());
// Since the block cache is large enough, all the blocks are cached. we
// do not need to lookup the seondary cache.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
Destroy(options);
}
TEST_F(DBSecondaryCacheTest, SecondaryCacheIntensiveTesting) {
LRUCacheOptions opts(8 * 1024, 0, false, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.env = fault_env_.get();
fault_fs_->SetFailGetUniqueId(true);
DestroyAndReopen(options);
std::string session_id;
ASSERT_OK(db_->GetDbSessionId(session_id));
secondary_cache->SetDbSessionId(session_id);
Random rnd(301);
const int N = 256;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(1000);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
Compact("a", "z");
Random r_index(47);
std::string v;
for (int i = 0; i < 1000; i++) {
uint32_t key_i = r_index.Next() % N;
v = Get(Key(key_i));
}
// We have over 200 data blocks there will be multiple insertion
// and lookups.
ASSERT_GE(secondary_cache->num_inserts(), 1u);
ASSERT_GE(secondary_cache->num_lookups(), 1u);
Destroy(options);
}
// In this test, the block cache size is set to 4096, after insert 6 KV-pairs
// and flush, there are 5 blocks in this SST file, 2 data blocks and 3 meta
// blocks. block_1 size is 4096 and block_2 size is 2056. The total size
// of the meta blocks are about 900 to 1000. Therefore, in any situation,
// if we try to insert block_1 to the block cache, it will always fails. Only
// block_2 will be successfully inserted into the block cache.
TEST_F(DBSecondaryCacheTest, SecondaryCacheFailureTest) {
LRUCacheOptions opts(4 * 1024, 0, false, 0.5, nullptr,
kDefaultToAdaptiveMutex, kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.paranoid_file_checks = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.env = fault_env_.get();
fault_fs_->SetFailGetUniqueId(true);
DestroyAndReopen(options);
std::string session_id;
ASSERT_OK(db_->GetDbSessionId(session_id));
secondary_cache->SetDbSessionId(session_id);
Random rnd(301);
const int N = 6;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(1007);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
// After Flush is successful, RocksDB do the paranoid check for the new
// SST file. Meta blocks are always cached in the block cache and they
// will not be evicted. When block_2 is cache miss and read out, it is
// inserted to the block cache. Note that, block_1 is never successfully
// inserted to the block cache. Here are 2 lookups in the secondary cache
// for block_1 and block_2
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 2u);
// Fail the insertion, in LRU cache, the secondary insertion returned status
// is not checked, therefore, the DB will not be influenced.
secondary_cache->InjectFailure();
Compact("a", "z");
// Compaction will create the iterator to scan the whole file. So all the
// blocks are needed. Meta blocks are always cached. When block_1 is read
// out, block_2 is evicted from block cache and inserted to secondary
// cache.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 3u);
std::string v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// The first data block is not in the cache, similarly, trigger the block
// cache Lookup and secondary cache lookup for block_1. But block_1 will not
// be inserted successfully due to the size. Currently, cache only has
// the meta blocks.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 4u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// The second data block is not in the cache, similarly, trigger the block
// cache Lookup and secondary cache lookup for block_2 and block_2 is found
// in the secondary cache. Now block cache has block_2
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
v = Get(Key(5));
ASSERT_EQ(1007, v.size());
// block_2 is in the block cache. There is a block cache hit. No need to
// lookup or insert the secondary cache.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 5u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// Lookup the first data block, not in the block cache, so lookup the
// secondary cache. Also not in the secondary cache. After Get, still
// block_1 is will not be cached.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 6u);
v = Get(Key(0));
ASSERT_EQ(1007, v.size());
// Lookup the first data block, not in the block cache, so lookup the
// secondary cache. Also not in the secondary cache. After Get, still
// block_1 is will not be cached.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 7u);
secondary_cache->ResetInjectFailure();
Destroy(options);
}
TEST_F(LRUSecondaryCacheTest, BasicWaitAllTest) {
LRUCacheOptions opts(1024, 2, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache =
std::make_shared<TestSecondaryCache>(32 * 1024);
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
const int num_keys = 32;
Random rnd(301);
std::vector<std::string> values;
for (int i = 0; i < num_keys; ++i) {
std::string str = rnd.RandomString(1020);
values.emplace_back(str);
TestItem* item = new TestItem(str.data(), str.length());
ASSERT_OK(cache->Insert("k" + std::to_string(i), item,
&LRUSecondaryCacheTest::helper_, str.length()));
}
// Force all entries to be evicted to the secondary cache
cache->SetCapacity(0);
ASSERT_EQ(secondary_cache->num_inserts(), 32u);
cache->SetCapacity(32 * 1024);
secondary_cache->SetResultMap(
{{"k3", TestSecondaryCache::ResultType::DEFER},
{"k4", TestSecondaryCache::ResultType::DEFER_AND_FAIL},
{"k5", TestSecondaryCache::ResultType::FAIL}});
std::vector<Cache::Handle*> results;
for (int i = 0; i < 6; ++i) {
results.emplace_back(
cache->Lookup("k" + std::to_string(i), &LRUSecondaryCacheTest::helper_,
test_item_creator, Cache::Priority::LOW, false));
}
cache->WaitAll(results);
for (int i = 0; i < 6; ++i) {
if (i == 4) {
ASSERT_EQ(cache->Value(results[i]), nullptr);
} else if (i == 5) {
ASSERT_EQ(results[i], nullptr);
continue;
} else {
TestItem* item = static_cast<TestItem*>(cache->Value(results[i]));
ASSERT_EQ(item->ToString(), values[i]);
}
cache->Release(results[i]);
}
cache.reset();
secondary_cache.reset();
}
// In this test, we have one KV pair per data block. We indirectly determine
// the cache key associated with each data block (and thus each KV) by using
// a sync point callback in TestSecondaryCache::Lookup. We then control the
// lookup result by setting the ResultMap.
TEST_F(DBSecondaryCacheTest, TestSecondaryCacheMultiGet) {
LRUCacheOptions opts(1 << 20, 0, false, 0.5, nullptr, kDefaultToAdaptiveMutex,
kDontChargeCacheMetadata);
std::shared_ptr<TestSecondaryCache> secondary_cache(
new TestSecondaryCache(2048 * 1024));
opts.secondary_cache = secondary_cache;
std::shared_ptr<Cache> cache = NewLRUCache(opts);
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.block_size = 4 * 1024;
table_options.cache_index_and_filter_blocks = false;
Options options = GetDefaultOptions();
options.create_if_missing = true;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.paranoid_file_checks = true;
DestroyAndReopen(options);
Random rnd(301);
const int N = 8;
std::vector<std::string> keys;
for (int i = 0; i < N; i++) {
std::string p_v = rnd.RandomString(4000);
keys.emplace_back(p_v);
ASSERT_OK(Put(Key(i), p_v));
}
ASSERT_OK(Flush());
// After Flush is successful, RocksDB does the paranoid check for the new
// SST file. This will try to lookup all data blocks in the secondary
// cache.
ASSERT_EQ(secondary_cache->num_inserts(), 0u);
ASSERT_EQ(secondary_cache->num_lookups(), 8u);
cache->SetCapacity(0);
ASSERT_EQ(secondary_cache->num_inserts(), 8u);
cache->SetCapacity(1 << 20);
std::vector<std::string> cache_keys;
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"TestSecondaryCache::Lookup", [&cache_keys](void* key) -> void {
cache_keys.emplace_back(*(static_cast<std::string*>(key)));
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
for (int i = 0; i < N; ++i) {
std::string v = Get(Key(i));
ASSERT_EQ(4000, v.size());
ASSERT_EQ(v, keys[i]);
}
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
ASSERT_EQ(secondary_cache->num_lookups(), 16u);
cache->SetCapacity(0);
cache->SetCapacity(1 << 20);
ASSERT_EQ(Get(Key(2)), keys[2]);
ASSERT_EQ(Get(Key(7)), keys[7]);
secondary_cache->SetResultMap(
{{cache_keys[3], TestSecondaryCache::ResultType::DEFER},
{cache_keys[4], TestSecondaryCache::ResultType::DEFER_AND_FAIL},
{cache_keys[5], TestSecondaryCache::ResultType::FAIL}});
std::vector<std::string> mget_keys(
{Key(0), Key(1), Key(2), Key(3), Key(4), Key(5), Key(6), Key(7)});
std::vector<PinnableSlice> values(mget_keys.size());
std::vector<Status> s(keys.size());
std::vector<Slice> key_slices;
for (const std::string& key : mget_keys) {
key_slices.emplace_back(key);
}
uint32_t num_lookups = secondary_cache->num_lookups();
dbfull()->MultiGet(ReadOptions(), dbfull()->DefaultColumnFamily(),
key_slices.size(), key_slices.data(), values.data(),
s.data(), false);
ASSERT_EQ(secondary_cache->num_lookups(), num_lookups + 5);
for (int i = 0; i < N; ++i) {
ASSERT_OK(s[i]);
ASSERT_EQ(values[i].ToString(), keys[i]);
values[i].Reset();
}
Destroy(options);
}
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}