rocksdb/db/db_block_cache_test.cc
Guido Tagliavini Ponce 9645e66fc9 Temporarily return a LRUCache from NewClockCache (#10351)
Summary:
ClockCache is still in experimental stage, and currently fails some pre-release fbcode tests. See https://www.internalfb.com/diff/D37772011. API calls to construct ClockCache are done via the function NewClockCache. For now, NewClockCache calls will return an LRUCache (with appropriate arguments), which is stable.

The idea that NewClockCache returns nullptr was also floated, but this would be interpreted as unsupported cache, and a default LRUCache would be constructed instead, potentially causing a performance regression that is harder to identify.

A new version of the NewClockCache function was created for our internal tests.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10351

Test Plan: ``make -j24 check`` and re-run the pre-release tests.

Reviewed By: pdillinger

Differential Revision: D37802685

Pulled By: guidotag

fbshipit-source-id: 0a8d10612ff21e576f7360cb13e20bc36e244972
2022-07-13 08:45:44 -07:00

2131 lines
80 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).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include <cstdlib>
#include <functional>
#include <memory>
#include <unordered_set>
#include "cache/cache_entry_roles.h"
#include "cache/cache_key.h"
#include "cache/clock_cache.h"
#include "cache/fast_lru_cache.h"
#include "cache/lru_cache.h"
#include "db/column_family.h"
#include "db/db_impl/db_impl.h"
#include "db/db_test_util.h"
#include "env/unique_id_gen.h"
#include "port/stack_trace.h"
#include "rocksdb/persistent_cache.h"
#include "rocksdb/statistics.h"
#include "rocksdb/table.h"
#include "rocksdb/table_properties.h"
#include "table/block_based/block_based_table_reader.h"
#include "table/unique_id_impl.h"
#include "util/compression.h"
#include "util/defer.h"
#include "util/hash.h"
#include "util/math.h"
#include "util/random.h"
#include "utilities/fault_injection_fs.h"
namespace ROCKSDB_NAMESPACE {
class DBBlockCacheTest : public DBTestBase {
private:
size_t miss_count_ = 0;
size_t hit_count_ = 0;
size_t insert_count_ = 0;
size_t failure_count_ = 0;
size_t compression_dict_miss_count_ = 0;
size_t compression_dict_hit_count_ = 0;
size_t compression_dict_insert_count_ = 0;
size_t compressed_miss_count_ = 0;
size_t compressed_hit_count_ = 0;
size_t compressed_insert_count_ = 0;
size_t compressed_failure_count_ = 0;
public:
const size_t kNumBlocks = 10;
const size_t kValueSize = 100;
DBBlockCacheTest()
: DBTestBase("db_block_cache_test", /*env_do_fsync=*/true) {}
BlockBasedTableOptions GetTableOptions() {
BlockBasedTableOptions table_options;
// Set a small enough block size so that each key-value get its own block.
table_options.block_size = 1;
return table_options;
}
Options GetOptions(const BlockBasedTableOptions& table_options) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.avoid_flush_during_recovery = false;
// options.compression = kNoCompression;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
return options;
}
void InitTable(const Options& /*options*/) {
std::string value(kValueSize, 'a');
for (size_t i = 0; i < kNumBlocks; i++) {
ASSERT_OK(Put(std::to_string(i), value.c_str()));
}
}
void RecordCacheCounters(const Options& options) {
miss_count_ = TestGetTickerCount(options, BLOCK_CACHE_MISS);
hit_count_ = TestGetTickerCount(options, BLOCK_CACHE_HIT);
insert_count_ = TestGetTickerCount(options, BLOCK_CACHE_ADD);
failure_count_ = TestGetTickerCount(options, BLOCK_CACHE_ADD_FAILURES);
compressed_miss_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS);
compressed_hit_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_HIT);
compressed_insert_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_ADD);
compressed_failure_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_ADD_FAILURES);
}
void RecordCacheCountersForCompressionDict(const Options& options) {
compression_dict_miss_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_MISS);
compression_dict_hit_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_HIT);
compression_dict_insert_count_ =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_ADD);
}
void CheckCacheCounters(const Options& options, size_t expected_misses,
size_t expected_hits, size_t expected_inserts,
size_t expected_failures) {
size_t new_miss_count = TestGetTickerCount(options, BLOCK_CACHE_MISS);
size_t new_hit_count = TestGetTickerCount(options, BLOCK_CACHE_HIT);
size_t new_insert_count = TestGetTickerCount(options, BLOCK_CACHE_ADD);
size_t new_failure_count =
TestGetTickerCount(options, BLOCK_CACHE_ADD_FAILURES);
ASSERT_EQ(miss_count_ + expected_misses, new_miss_count);
ASSERT_EQ(hit_count_ + expected_hits, new_hit_count);
ASSERT_EQ(insert_count_ + expected_inserts, new_insert_count);
ASSERT_EQ(failure_count_ + expected_failures, new_failure_count);
miss_count_ = new_miss_count;
hit_count_ = new_hit_count;
insert_count_ = new_insert_count;
failure_count_ = new_failure_count;
}
void CheckCacheCountersForCompressionDict(
const Options& options, size_t expected_compression_dict_misses,
size_t expected_compression_dict_hits,
size_t expected_compression_dict_inserts) {
size_t new_compression_dict_miss_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_MISS);
size_t new_compression_dict_hit_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_HIT);
size_t new_compression_dict_insert_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_ADD);
ASSERT_EQ(compression_dict_miss_count_ + expected_compression_dict_misses,
new_compression_dict_miss_count);
ASSERT_EQ(compression_dict_hit_count_ + expected_compression_dict_hits,
new_compression_dict_hit_count);
ASSERT_EQ(
compression_dict_insert_count_ + expected_compression_dict_inserts,
new_compression_dict_insert_count);
compression_dict_miss_count_ = new_compression_dict_miss_count;
compression_dict_hit_count_ = new_compression_dict_hit_count;
compression_dict_insert_count_ = new_compression_dict_insert_count;
}
void CheckCompressedCacheCounters(const Options& options,
size_t expected_misses,
size_t expected_hits,
size_t expected_inserts,
size_t expected_failures) {
size_t new_miss_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS);
size_t new_hit_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_HIT);
size_t new_insert_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_ADD);
size_t new_failure_count =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_ADD_FAILURES);
ASSERT_EQ(compressed_miss_count_ + expected_misses, new_miss_count);
ASSERT_EQ(compressed_hit_count_ + expected_hits, new_hit_count);
ASSERT_EQ(compressed_insert_count_ + expected_inserts, new_insert_count);
ASSERT_EQ(compressed_failure_count_ + expected_failures, new_failure_count);
compressed_miss_count_ = new_miss_count;
compressed_hit_count_ = new_hit_count;
compressed_insert_count_ = new_insert_count;
compressed_failure_count_ = new_failure_count;
}
#ifndef ROCKSDB_LITE
const std::array<size_t, kNumCacheEntryRoles> GetCacheEntryRoleCountsBg() {
// Verify in cache entry role stats
ColumnFamilyHandleImpl* cfh =
static_cast<ColumnFamilyHandleImpl*>(dbfull()->DefaultColumnFamily());
InternalStats* internal_stats_ptr = cfh->cfd()->internal_stats();
InternalStats::CacheEntryRoleStats stats;
internal_stats_ptr->TEST_GetCacheEntryRoleStats(&stats,
/*foreground=*/false);
return stats.entry_counts;
}
#endif // ROCKSDB_LITE
};
TEST_F(DBBlockCacheTest, IteratorBlockCacheUsage) {
ReadOptions read_options;
read_options.fill_cache = false;
auto table_options = GetTableOptions();
auto options = GetOptions(table_options);
InitTable(options);
LRUCacheOptions co;
co.capacity = 0;
co.num_shard_bits = 0;
co.strict_capacity_limit = false;
// Needed not to count entry stats collector
co.metadata_charge_policy = kDontChargeCacheMetadata;
std::shared_ptr<Cache> cache = NewLRUCache(co);
table_options.block_cache = cache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
RecordCacheCounters(options);
std::vector<std::unique_ptr<Iterator>> iterators(kNumBlocks - 1);
Iterator* iter = nullptr;
ASSERT_EQ(0, cache->GetUsage());
iter = db_->NewIterator(read_options);
iter->Seek(std::to_string(0));
ASSERT_LT(0, cache->GetUsage());
delete iter;
iter = nullptr;
ASSERT_EQ(0, cache->GetUsage());
}
TEST_F(DBBlockCacheTest, TestWithoutCompressedBlockCache) {
ReadOptions read_options;
auto table_options = GetTableOptions();
auto options = GetOptions(table_options);
InitTable(options);
LRUCacheOptions co;
co.capacity = 0;
co.num_shard_bits = 0;
co.strict_capacity_limit = false;
// Needed not to count entry stats collector
co.metadata_charge_policy = kDontChargeCacheMetadata;
std::shared_ptr<Cache> cache = NewLRUCache(co);
table_options.block_cache = cache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
RecordCacheCounters(options);
std::vector<std::unique_ptr<Iterator>> iterators(kNumBlocks - 1);
Iterator* iter = nullptr;
// Load blocks into cache.
for (size_t i = 0; i + 1 < kNumBlocks; i++) {
iter = db_->NewIterator(read_options);
iter->Seek(std::to_string(i));
ASSERT_OK(iter->status());
CheckCacheCounters(options, 1, 0, 1, 0);
iterators[i].reset(iter);
}
size_t usage = cache->GetUsage();
ASSERT_LT(0, usage);
cache->SetCapacity(usage);
ASSERT_EQ(usage, cache->GetPinnedUsage());
// Test with strict capacity limit.
cache->SetStrictCapacityLimit(true);
iter = db_->NewIterator(read_options);
iter->Seek(std::to_string(kNumBlocks - 1));
ASSERT_TRUE(iter->status().IsMemoryLimit());
CheckCacheCounters(options, 1, 0, 0, 1);
delete iter;
iter = nullptr;
// Release iterators and access cache again.
for (size_t i = 0; i + 1 < kNumBlocks; i++) {
iterators[i].reset();
CheckCacheCounters(options, 0, 0, 0, 0);
}
ASSERT_EQ(0, cache->GetPinnedUsage());
for (size_t i = 0; i + 1 < kNumBlocks; i++) {
iter = db_->NewIterator(read_options);
iter->Seek(std::to_string(i));
ASSERT_OK(iter->status());
CheckCacheCounters(options, 0, 1, 0, 0);
iterators[i].reset(iter);
}
}
#ifdef SNAPPY
TEST_F(DBBlockCacheTest, TestWithCompressedBlockCache) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.no_block_cache = true;
table_options.block_cache_compressed = nullptr;
table_options.block_size = 1;
table_options.filter_policy.reset(NewBloomFilterPolicy(20));
table_options.cache_index_and_filter_blocks = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.compression = CompressionType::kSnappyCompression;
DestroyAndReopen(options);
std::string value(kValueSize, 'a');
for (size_t i = 0; i < kNumBlocks; i++) {
ASSERT_OK(Put(std::to_string(i), value));
ASSERT_OK(Flush());
}
ReadOptions read_options;
std::shared_ptr<Cache> compressed_cache = NewLRUCache(1 << 25, 0, false);
LRUCacheOptions co;
co.capacity = 0;
co.num_shard_bits = 0;
co.strict_capacity_limit = false;
// Needed not to count entry stats collector
co.metadata_charge_policy = kDontChargeCacheMetadata;
std::shared_ptr<Cache> cache = NewLRUCache(co);
table_options.block_cache = cache;
table_options.no_block_cache = false;
table_options.block_cache_compressed = compressed_cache;
table_options.max_auto_readahead_size = 0;
table_options.cache_index_and_filter_blocks = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
RecordCacheCounters(options);
// Load blocks into cache.
for (size_t i = 0; i < kNumBlocks - 1; i++) {
ASSERT_EQ(value, Get(std::to_string(i)));
CheckCacheCounters(options, 1, 0, 1, 0);
CheckCompressedCacheCounters(options, 1, 0, 1, 0);
}
size_t usage = cache->GetUsage();
ASSERT_EQ(0, usage);
ASSERT_EQ(usage, cache->GetPinnedUsage());
size_t compressed_usage = compressed_cache->GetUsage();
ASSERT_LT(0, compressed_usage);
// Compressed block cache cannot be pinned.
ASSERT_EQ(0, compressed_cache->GetPinnedUsage());
// Set strict capacity limit flag. Now block will only load into compressed
// block cache.
cache->SetCapacity(usage);
cache->SetStrictCapacityLimit(true);
ASSERT_EQ(usage, cache->GetPinnedUsage());
// Load last key block.
ASSERT_EQ(
"Operation aborted: Memory limit reached: Insert failed due to LRU cache "
"being full.",
Get(std::to_string(kNumBlocks - 1)));
// Failure will also record the miss counter.
CheckCacheCounters(options, 1, 0, 0, 1);
CheckCompressedCacheCounters(options, 1, 0, 1, 0);
// Clear strict capacity limit flag. This time we shall hit compressed block
// cache and load into block cache.
cache->SetStrictCapacityLimit(false);
// Load last key block.
ASSERT_EQ(value, Get(std::to_string(kNumBlocks - 1)));
CheckCacheCounters(options, 1, 0, 1, 0);
CheckCompressedCacheCounters(options, 0, 1, 0, 0);
}
namespace {
class PersistentCacheFromCache : public PersistentCache {
public:
PersistentCacheFromCache(std::shared_ptr<Cache> cache, bool read_only)
: cache_(cache), read_only_(read_only) {}
Status Insert(const Slice& key, const char* data,
const size_t size) override {
if (read_only_) {
return Status::NotSupported();
}
std::unique_ptr<char[]> copy{new char[size]};
std::copy_n(data, size, copy.get());
Status s = cache_->Insert(
key, copy.get(), size,
GetCacheEntryDeleterForRole<char[], CacheEntryRole::kMisc>());
if (s.ok()) {
copy.release();
}
return s;
}
Status Lookup(const Slice& key, std::unique_ptr<char[]>* data,
size_t* size) override {
auto handle = cache_->Lookup(key);
if (handle) {
char* ptr = static_cast<char*>(cache_->Value(handle));
*size = cache_->GetCharge(handle);
data->reset(new char[*size]);
std::copy_n(ptr, *size, data->get());
cache_->Release(handle);
return Status::OK();
} else {
return Status::NotFound();
}
}
bool IsCompressed() override { return false; }
StatsType Stats() override { return StatsType(); }
std::string GetPrintableOptions() const override { return ""; }
uint64_t NewId() override { return cache_->NewId(); }
private:
std::shared_ptr<Cache> cache_;
bool read_only_;
};
class ReadOnlyCacheWrapper : public CacheWrapper {
using CacheWrapper::CacheWrapper;
using Cache::Insert;
Status Insert(const Slice& /*key*/, void* /*value*/, size_t /*charge*/,
void (*)(const Slice& key, void* value) /*deleter*/,
Handle** /*handle*/, Priority /*priority*/) override {
return Status::NotSupported();
}
};
} // namespace
TEST_F(DBBlockCacheTest, TestWithSameCompressed) {
auto table_options = GetTableOptions();
auto options = GetOptions(table_options);
InitTable(options);
std::shared_ptr<Cache> rw_cache{NewLRUCache(1000000)};
std::shared_ptr<PersistentCacheFromCache> rw_pcache{
new PersistentCacheFromCache(rw_cache, /*read_only*/ false)};
// Exercise some obscure behavior with read-only wrappers
std::shared_ptr<Cache> ro_cache{new ReadOnlyCacheWrapper(rw_cache)};
std::shared_ptr<PersistentCacheFromCache> ro_pcache{
new PersistentCacheFromCache(rw_cache, /*read_only*/ true)};
// Simple same pointer
table_options.block_cache = rw_cache;
table_options.block_cache_compressed = rw_cache;
table_options.persistent_cache.reset();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: block_cache same as block_cache_compressed not "
"currently supported, and would be bad for performance anyway");
// Other cases
table_options.block_cache = ro_cache;
table_options.block_cache_compressed = rw_cache;
table_options.persistent_cache.reset();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: block_cache and block_cache_compressed share "
"the same key space, which is not supported");
table_options.block_cache = rw_cache;
table_options.block_cache_compressed = ro_cache;
table_options.persistent_cache.reset();
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: block_cache_compressed and block_cache share "
"the same key space, which is not supported");
table_options.block_cache = ro_cache;
table_options.block_cache_compressed.reset();
table_options.persistent_cache = rw_pcache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: block_cache and persistent_cache share the same "
"key space, which is not supported");
table_options.block_cache = rw_cache;
table_options.block_cache_compressed.reset();
table_options.persistent_cache = ro_pcache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: persistent_cache and block_cache share the same "
"key space, which is not supported");
table_options.block_cache.reset();
table_options.no_block_cache = true;
table_options.block_cache_compressed = ro_cache;
table_options.persistent_cache = rw_pcache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: block_cache_compressed and persistent_cache "
"share the same key space, which is not supported");
table_options.block_cache.reset();
table_options.no_block_cache = true;
table_options.block_cache_compressed = rw_cache;
table_options.persistent_cache = ro_pcache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
ASSERT_EQ(TryReopen(options).ToString(),
"Invalid argument: persistent_cache and block_cache_compressed "
"share the same key space, which is not supported");
}
#endif // SNAPPY
#ifndef ROCKSDB_LITE
// Make sure that when options.block_cache is set, after a new table is
// created its index/filter blocks are added to block cache.
TEST_F(DBBlockCacheTest, IndexAndFilterBlocksOfNewTableAddedToCache) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = true;
table_options.filter_policy.reset(NewBloomFilterPolicy(20));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
CreateAndReopenWithCF({"pikachu"}, options);
ASSERT_OK(Put(1, "key", "val"));
// Create a new table.
ASSERT_OK(Flush(1));
// index/filter blocks added to block cache right after table creation.
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(2, /* only index/filter were added */
TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_MISS));
uint64_t int_num;
ASSERT_TRUE(
dbfull()->GetIntProperty("rocksdb.estimate-table-readers-mem", &int_num));
ASSERT_EQ(int_num, 0U);
// Make sure filter block is in cache.
std::string value;
ReadOptions ropt;
db_->KeyMayExist(ReadOptions(), handles_[1], "key", &value);
// Miss count should remain the same.
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_HIT));
db_->KeyMayExist(ReadOptions(), handles_[1], "key", &value);
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_FILTER_HIT));
// Make sure index block is in cache.
auto index_block_hit = TestGetTickerCount(options, BLOCK_CACHE_INDEX_HIT);
value = Get(1, "key");
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(index_block_hit + 1,
TestGetTickerCount(options, BLOCK_CACHE_INDEX_HIT));
value = Get(1, "key");
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(index_block_hit + 2,
TestGetTickerCount(options, BLOCK_CACHE_INDEX_HIT));
}
// With fill_cache = false, fills up the cache, then iterates over the entire
// db, verify dummy entries inserted in `BlockBasedTable::NewDataBlockIterator`
// does not cause heap-use-after-free errors in COMPILE_WITH_ASAN=1 runs
TEST_F(DBBlockCacheTest, FillCacheAndIterateDB) {
ReadOptions read_options;
read_options.fill_cache = false;
auto table_options = GetTableOptions();
auto options = GetOptions(table_options);
InitTable(options);
std::shared_ptr<Cache> cache = NewLRUCache(10, 0, true);
table_options.block_cache = cache;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
ASSERT_OK(Put("key1", "val1"));
ASSERT_OK(Put("key2", "val2"));
ASSERT_OK(Flush());
ASSERT_OK(Put("key3", "val3"));
ASSERT_OK(Put("key4", "val4"));
ASSERT_OK(Flush());
ASSERT_OK(Put("key5", "val5"));
ASSERT_OK(Put("key6", "val6"));
ASSERT_OK(Flush());
Iterator* iter = nullptr;
iter = db_->NewIterator(read_options);
iter->Seek(std::to_string(0));
while (iter->Valid()) {
iter->Next();
}
delete iter;
iter = nullptr;
}
TEST_F(DBBlockCacheTest, IndexAndFilterBlocksStats) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = true;
LRUCacheOptions co;
// 500 bytes are enough to hold the first two blocks
co.capacity = 500;
co.num_shard_bits = 0;
co.strict_capacity_limit = false;
co.metadata_charge_policy = kDontChargeCacheMetadata;
std::shared_ptr<Cache> cache = NewLRUCache(co);
table_options.block_cache = cache;
table_options.filter_policy.reset(NewBloomFilterPolicy(20, true));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
CreateAndReopenWithCF({"pikachu"}, options);
ASSERT_OK(Put(1, "longer_key", "val"));
// Create a new table
ASSERT_OK(Flush(1));
size_t index_bytes_insert =
TestGetTickerCount(options, BLOCK_CACHE_INDEX_BYTES_INSERT);
size_t filter_bytes_insert =
TestGetTickerCount(options, BLOCK_CACHE_FILTER_BYTES_INSERT);
ASSERT_GT(index_bytes_insert, 0);
ASSERT_GT(filter_bytes_insert, 0);
ASSERT_EQ(cache->GetUsage(), index_bytes_insert + filter_bytes_insert);
// set the cache capacity to the current usage
cache->SetCapacity(index_bytes_insert + filter_bytes_insert);
// The index and filter eviction statistics were broken by the refactoring
// that moved the readers out of the block cache. Disabling these until we can
// bring the stats back.
// ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_INDEX_BYTES_EVICT), 0);
// ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_FILTER_BYTES_EVICT), 0);
// Note that the second key needs to be no longer than the first one.
// Otherwise the second index block may not fit in cache.
ASSERT_OK(Put(1, "key", "val"));
// Create a new table
ASSERT_OK(Flush(1));
// cache evicted old index and block entries
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_INDEX_BYTES_INSERT),
index_bytes_insert);
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_FILTER_BYTES_INSERT),
filter_bytes_insert);
// The index and filter eviction statistics were broken by the refactoring
// that moved the readers out of the block cache. Disabling these until we can
// bring the stats back.
// ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_INDEX_BYTES_EVICT),
// index_bytes_insert);
// ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_FILTER_BYTES_EVICT),
// filter_bytes_insert);
}
#if (defined OS_LINUX || defined OS_WIN)
TEST_F(DBBlockCacheTest, WarmCacheWithDataBlocksDuringFlush) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.block_cache = NewLRUCache(1 << 25, 0, false);
table_options.cache_index_and_filter_blocks = false;
table_options.prepopulate_block_cache =
BlockBasedTableOptions::PrepopulateBlockCache::kFlushOnly;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
std::string value(kValueSize, 'a');
for (size_t i = 1; i <= kNumBlocks; i++) {
ASSERT_OK(Put(std::to_string(i), value));
ASSERT_OK(Flush());
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(value, Get(std::to_string(i)));
ASSERT_EQ(0, options.statistics->getTickerCount(BLOCK_CACHE_DATA_MISS));
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_DATA_HIT));
}
// Verify compaction not counted
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
/*end=*/nullptr));
EXPECT_EQ(kNumBlocks,
options.statistics->getTickerCount(BLOCK_CACHE_DATA_ADD));
}
// This test cache data, index and filter blocks during flush.
class DBBlockCacheTest1 : public DBTestBase,
public ::testing::WithParamInterface<uint32_t> {
public:
const size_t kNumBlocks = 10;
const size_t kValueSize = 100;
DBBlockCacheTest1() : DBTestBase("db_block_cache_test1", true) {}
};
INSTANTIATE_TEST_CASE_P(DBBlockCacheTest1, DBBlockCacheTest1,
::testing::Values(1, 2));
TEST_P(DBBlockCacheTest1, WarmCacheWithBlocksDuringFlush) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.max_compaction_bytes = 2000;
BlockBasedTableOptions table_options;
table_options.block_cache = NewLRUCache(1 << 25, 0, false);
uint32_t filter_type = GetParam();
switch (filter_type) {
case 1: // partition_filter
table_options.partition_filters = true;
table_options.index_type =
BlockBasedTableOptions::IndexType::kTwoLevelIndexSearch;
table_options.filter_policy.reset(NewBloomFilterPolicy(10));
break;
case 2: // full filter
table_options.filter_policy.reset(NewBloomFilterPolicy(10));
break;
default:
assert(false);
}
table_options.cache_index_and_filter_blocks = true;
table_options.prepopulate_block_cache =
BlockBasedTableOptions::PrepopulateBlockCache::kFlushOnly;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
std::string value(kValueSize, 'a');
for (size_t i = 1; i <= kNumBlocks; i++) {
ASSERT_OK(Put(std::to_string(i), value));
ASSERT_OK(Flush());
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_DATA_ADD));
if (filter_type == 1) {
ASSERT_EQ(2 * i,
options.statistics->getTickerCount(BLOCK_CACHE_INDEX_ADD));
ASSERT_EQ(2 * i,
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_ADD));
} else {
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_INDEX_ADD));
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_FILTER_ADD));
}
ASSERT_EQ(value, Get(std::to_string(i)));
ASSERT_EQ(0, options.statistics->getTickerCount(BLOCK_CACHE_DATA_MISS));
ASSERT_EQ(i, options.statistics->getTickerCount(BLOCK_CACHE_DATA_HIT));
ASSERT_EQ(0, options.statistics->getTickerCount(BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(i * 3, options.statistics->getTickerCount(BLOCK_CACHE_INDEX_HIT));
if (filter_type == 1) {
ASSERT_EQ(i * 3,
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_HIT));
} else {
ASSERT_EQ(i * 2,
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_HIT));
}
ASSERT_EQ(0, options.statistics->getTickerCount(BLOCK_CACHE_FILTER_MISS));
}
// Verify compaction not counted
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
/*end=*/nullptr));
EXPECT_EQ(kNumBlocks,
options.statistics->getTickerCount(BLOCK_CACHE_DATA_ADD));
// Index and filter blocks are automatically warmed when the new table file
// is automatically opened at the end of compaction. This is not easily
// disabled so results in the new index and filter blocks being warmed.
if (filter_type == 1) {
EXPECT_EQ(2 * (1 + kNumBlocks),
options.statistics->getTickerCount(BLOCK_CACHE_INDEX_ADD));
EXPECT_EQ(2 * (1 + kNumBlocks),
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_ADD));
} else {
EXPECT_EQ(1 + kNumBlocks,
options.statistics->getTickerCount(BLOCK_CACHE_INDEX_ADD));
EXPECT_EQ(1 + kNumBlocks,
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_ADD));
}
}
TEST_F(DBBlockCacheTest, DynamicallyWarmCacheDuringFlush) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.block_cache = NewLRUCache(1 << 25, 0, false);
table_options.cache_index_and_filter_blocks = false;
table_options.prepopulate_block_cache =
BlockBasedTableOptions::PrepopulateBlockCache::kFlushOnly;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
std::string value(kValueSize, 'a');
for (size_t i = 1; i <= 5; i++) {
ASSERT_OK(Put(std::to_string(i), value));
ASSERT_OK(Flush());
ASSERT_EQ(1,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(value, Get(std::to_string(i)));
ASSERT_EQ(0,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(
0, options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_MISS));
ASSERT_EQ(1,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_HIT));
}
ASSERT_OK(dbfull()->SetOptions(
{{"block_based_table_factory", "{prepopulate_block_cache=kDisable;}"}}));
for (size_t i = 6; i <= kNumBlocks; i++) {
ASSERT_OK(Put(std::to_string(i), value));
ASSERT_OK(Flush());
ASSERT_EQ(0,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(value, Get(std::to_string(i)));
ASSERT_EQ(1,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(
1, options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_MISS));
ASSERT_EQ(0,
options.statistics->getAndResetTickerCount(BLOCK_CACHE_DATA_HIT));
}
}
#endif
namespace {
// A mock cache wraps LRUCache, and record how many entries have been
// inserted for each priority.
class MockCache : public LRUCache {
public:
static uint32_t high_pri_insert_count;
static uint32_t low_pri_insert_count;
MockCache()
: LRUCache((size_t)1 << 25 /*capacity*/, 0 /*num_shard_bits*/,
false /*strict_capacity_limit*/, 0.0 /*high_pri_pool_ratio*/) {
}
using ShardedCache::Insert;
Status Insert(const Slice& key, void* value,
const Cache::CacheItemHelper* helper_cb, size_t charge,
Handle** handle, Priority priority) override {
DeleterFn delete_cb = helper_cb->del_cb;
if (priority == Priority::LOW) {
low_pri_insert_count++;
} else {
high_pri_insert_count++;
}
return LRUCache::Insert(key, value, charge, delete_cb, handle, priority);
}
};
uint32_t MockCache::high_pri_insert_count = 0;
uint32_t MockCache::low_pri_insert_count = 0;
} // anonymous namespace
TEST_F(DBBlockCacheTest, IndexAndFilterBlocksCachePriority) {
for (auto priority : {Cache::Priority::LOW, Cache::Priority::HIGH}) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = true;
table_options.block_cache.reset(new MockCache());
table_options.filter_policy.reset(NewBloomFilterPolicy(20));
table_options.cache_index_and_filter_blocks_with_high_priority =
priority == Cache::Priority::HIGH ? true : false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
MockCache::high_pri_insert_count = 0;
MockCache::low_pri_insert_count = 0;
// Create a new table.
ASSERT_OK(Put("foo", "value"));
ASSERT_OK(Put("bar", "value"));
ASSERT_OK(Flush());
ASSERT_EQ(1, NumTableFilesAtLevel(0));
// index/filter blocks added to block cache right after table creation.
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(2, /* only index/filter were added */
TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_MISS));
if (priority == Cache::Priority::LOW) {
ASSERT_EQ(0u, MockCache::high_pri_insert_count);
ASSERT_EQ(2u, MockCache::low_pri_insert_count);
} else {
ASSERT_EQ(2u, MockCache::high_pri_insert_count);
ASSERT_EQ(0u, MockCache::low_pri_insert_count);
}
// Access data block.
ASSERT_EQ("value", Get("foo"));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(3, /*adding data block*/
TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_DATA_MISS));
// Data block should be inserted with low priority.
if (priority == Cache::Priority::LOW) {
ASSERT_EQ(0u, MockCache::high_pri_insert_count);
ASSERT_EQ(3u, MockCache::low_pri_insert_count);
} else {
ASSERT_EQ(2u, MockCache::high_pri_insert_count);
ASSERT_EQ(1u, MockCache::low_pri_insert_count);
}
}
}
namespace {
// An LRUCache wrapper that can falsely report "not found" on Lookup.
// This allows us to manipulate BlockBasedTableReader into thinking
// another thread inserted the data in between Lookup and Insert,
// while mostly preserving the LRUCache interface/behavior.
class LookupLiarCache : public CacheWrapper {
int nth_lookup_not_found_ = 0;
public:
explicit LookupLiarCache(std::shared_ptr<Cache> target)
: CacheWrapper(std::move(target)) {}
using Cache::Lookup;
Handle* Lookup(const Slice& key, Statistics* stats) override {
if (nth_lookup_not_found_ == 1) {
nth_lookup_not_found_ = 0;
return nullptr;
}
if (nth_lookup_not_found_ > 1) {
--nth_lookup_not_found_;
}
return CacheWrapper::Lookup(key, stats);
}
// 1 == next lookup, 2 == after next, etc.
void SetNthLookupNotFound(int n) { nth_lookup_not_found_ = n; }
};
} // anonymous namespace
TEST_F(DBBlockCacheTest, AddRedundantStats) {
const size_t capacity = size_t{1} << 25;
const int num_shard_bits = 0; // 1 shard
int iterations_tested = 0;
for (std::shared_ptr<Cache> base_cache :
{NewLRUCache(capacity, num_shard_bits),
ExperimentalNewClockCache(
capacity, 1 /*estimated_value_size*/, num_shard_bits,
false /*strict_capacity_limit*/, kDefaultCacheMetadataChargePolicy),
NewFastLRUCache(capacity, 1 /*estimated_value_size*/, num_shard_bits,
false /*strict_capacity_limit*/,
kDefaultCacheMetadataChargePolicy)}) {
if (!base_cache) {
// Skip clock cache when not supported
continue;
}
++iterations_tested;
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
std::shared_ptr<LookupLiarCache> cache =
std::make_shared<LookupLiarCache>(base_cache);
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = true;
table_options.block_cache = cache;
table_options.filter_policy.reset(NewBloomFilterPolicy(50));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
// Create a new table.
ASSERT_OK(Put("foo", "value"));
ASSERT_OK(Put("bar", "value"));
ASSERT_OK(Flush());
ASSERT_EQ(1, NumTableFilesAtLevel(0));
// Normal access filter+index+data.
ASSERT_EQ("value", Get("foo"));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD));
// --------
ASSERT_EQ(3, TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD_REDUNDANT));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD_REDUNDANT));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD_REDUNDANT));
// --------
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_ADD_REDUNDANT));
// Againt access filter+index+data, but force redundant load+insert on index
cache->SetNthLookupNotFound(2);
ASSERT_EQ("value", Get("bar"));
ASSERT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD));
// --------
ASSERT_EQ(4, TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD_REDUNDANT));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD_REDUNDANT));
ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD_REDUNDANT));
// --------
ASSERT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_ADD_REDUNDANT));
// Access just filter (with high probability), and force redundant
// load+insert
cache->SetNthLookupNotFound(1);
ASSERT_EQ("NOT_FOUND", Get("this key was not added"));
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD));
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD));
// --------
EXPECT_EQ(5, TestGetTickerCount(options, BLOCK_CACHE_ADD));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD_REDUNDANT));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD_REDUNDANT));
EXPECT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD_REDUNDANT));
// --------
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_ADD_REDUNDANT));
// Access just data, forcing redundant load+insert
ReadOptions read_options;
std::unique_ptr<Iterator> iter{db_->NewIterator(read_options)};
cache->SetNthLookupNotFound(1);
iter->SeekToFirst();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key(), "bar");
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD));
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD));
EXPECT_EQ(2, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD));
// --------
EXPECT_EQ(6, TestGetTickerCount(options, BLOCK_CACHE_ADD));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_INDEX_ADD_REDUNDANT));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_FILTER_ADD_REDUNDANT));
EXPECT_EQ(1, TestGetTickerCount(options, BLOCK_CACHE_DATA_ADD_REDUNDANT));
// --------
EXPECT_EQ(3, TestGetTickerCount(options, BLOCK_CACHE_ADD_REDUNDANT));
}
EXPECT_GE(iterations_tested, 1);
}
TEST_F(DBBlockCacheTest, ParanoidFileChecks) {
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.level0_file_num_compaction_trigger = 2;
options.paranoid_file_checks = true;
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = false;
table_options.filter_policy.reset(NewBloomFilterPolicy(20));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
CreateAndReopenWithCF({"pikachu"}, options);
ASSERT_OK(Put(1, "1_key", "val"));
ASSERT_OK(Put(1, "9_key", "val"));
// Create a new table.
ASSERT_OK(Flush(1));
ASSERT_EQ(1, /* read and cache data block */
TestGetTickerCount(options, BLOCK_CACHE_ADD));
ASSERT_OK(Put(1, "1_key2", "val2"));
ASSERT_OK(Put(1, "9_key2", "val2"));
// Create a new SST file. This will further trigger a compaction
// and generate another file.
ASSERT_OK(Flush(1));
ASSERT_OK(dbfull()->TEST_WaitForCompact());
ASSERT_EQ(3, /* Totally 3 files created up to now */
TestGetTickerCount(options, BLOCK_CACHE_ADD));
// After disabling options.paranoid_file_checks. NO further block
// is added after generating a new file.
ASSERT_OK(
dbfull()->SetOptions(handles_[1], {{"paranoid_file_checks", "false"}}));
ASSERT_OK(Put(1, "1_key3", "val3"));
ASSERT_OK(Put(1, "9_key3", "val3"));
ASSERT_OK(Flush(1));
ASSERT_OK(Put(1, "1_key4", "val4"));
ASSERT_OK(Put(1, "9_key4", "val4"));
ASSERT_OK(Flush(1));
ASSERT_OK(dbfull()->TEST_WaitForCompact());
ASSERT_EQ(3, /* Totally 3 files created up to now */
TestGetTickerCount(options, BLOCK_CACHE_ADD));
}
TEST_F(DBBlockCacheTest, CompressedCache) {
if (!Snappy_Supported()) {
return;
}
int num_iter = 80;
// Run this test three iterations.
// Iteration 1: only a uncompressed block cache
// Iteration 2: only a compressed block cache
// Iteration 3: both block cache and compressed cache
// Iteration 4: both block cache and compressed cache, but DB is not
// compressed
for (int iter = 0; iter < 4; iter++) {
Options options = CurrentOptions();
options.write_buffer_size = 64 * 1024; // small write buffer
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
switch (iter) {
case 0:
// only uncompressed block cache
table_options.block_cache = NewLRUCache(8 * 1024);
table_options.block_cache_compressed = nullptr;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
break;
case 1:
// no block cache, only compressed cache
table_options.no_block_cache = true;
table_options.block_cache = nullptr;
table_options.block_cache_compressed = NewLRUCache(8 * 1024);
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
break;
case 2:
// both compressed and uncompressed block cache
table_options.block_cache = NewLRUCache(1024);
table_options.block_cache_compressed = NewLRUCache(8 * 1024);
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
break;
case 3:
// both block cache and compressed cache, but DB is not compressed
// also, make block cache sizes bigger, to trigger block cache hits
table_options.block_cache = NewLRUCache(1024 * 1024);
table_options.block_cache_compressed = NewLRUCache(8 * 1024 * 1024);
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.compression = kNoCompression;
break;
default:
FAIL();
}
CreateAndReopenWithCF({"pikachu"}, options);
// default column family doesn't have block cache
Options no_block_cache_opts;
no_block_cache_opts.statistics = options.statistics;
no_block_cache_opts = CurrentOptions(no_block_cache_opts);
BlockBasedTableOptions table_options_no_bc;
table_options_no_bc.no_block_cache = true;
no_block_cache_opts.table_factory.reset(
NewBlockBasedTableFactory(table_options_no_bc));
ReopenWithColumnFamilies(
{"default", "pikachu"},
std::vector<Options>({no_block_cache_opts, options}));
Random rnd(301);
// Write 8MB (80 values, each 100K)
ASSERT_EQ(NumTableFilesAtLevel(0, 1), 0);
std::vector<std::string> values;
std::string str;
for (int i = 0; i < num_iter; i++) {
if (i % 4 == 0) { // high compression ratio
str = rnd.RandomString(1000);
}
values.push_back(str);
ASSERT_OK(Put(1, Key(i), values[i]));
}
// flush all data from memtable so that reads are from block cache
ASSERT_OK(Flush(1));
for (int i = 0; i < num_iter; i++) {
ASSERT_EQ(Get(1, Key(i)), values[i]);
}
// check that we triggered the appropriate code paths in the cache
switch (iter) {
case 0:
// only uncompressed block cache
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_MISS), 0);
ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS), 0);
break;
case 1:
// no block cache, only compressed cache
ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_MISS), 0);
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS), 0);
break;
case 2:
// both compressed and uncompressed block cache
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_MISS), 0);
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS), 0);
break;
case 3:
// both compressed and uncompressed block cache
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_MISS), 0);
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_HIT), 0);
ASSERT_GT(TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_MISS), 0);
// compressed doesn't have any hits since blocks are not compressed on
// storage
ASSERT_EQ(TestGetTickerCount(options, BLOCK_CACHE_COMPRESSED_HIT), 0);
break;
default:
FAIL();
}
options.create_if_missing = true;
DestroyAndReopen(options);
}
}
TEST_F(DBBlockCacheTest, CacheCompressionDict) {
const int kNumFiles = 4;
const int kNumEntriesPerFile = 128;
const int kNumBytesPerEntry = 1024;
// Try all the available libraries that support dictionary compression
std::vector<CompressionType> compression_types;
if (Zlib_Supported()) {
compression_types.push_back(kZlibCompression);
}
if (LZ4_Supported()) {
compression_types.push_back(kLZ4Compression);
compression_types.push_back(kLZ4HCCompression);
}
if (ZSTD_Supported()) {
compression_types.push_back(kZSTD);
} else if (ZSTDNotFinal_Supported()) {
compression_types.push_back(kZSTDNotFinalCompression);
}
Random rnd(301);
for (auto compression_type : compression_types) {
Options options = CurrentOptions();
options.bottommost_compression = compression_type;
options.bottommost_compression_opts.max_dict_bytes = 4096;
options.bottommost_compression_opts.enabled = true;
options.create_if_missing = true;
options.num_levels = 2;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.target_file_size_base = kNumEntriesPerFile * kNumBytesPerEntry;
BlockBasedTableOptions table_options;
table_options.cache_index_and_filter_blocks = true;
table_options.block_cache.reset(new MockCache());
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
RecordCacheCountersForCompressionDict(options);
for (int i = 0; i < kNumFiles; ++i) {
ASSERT_EQ(i, NumTableFilesAtLevel(0, 0));
for (int j = 0; j < kNumEntriesPerFile; ++j) {
std::string value = rnd.RandomString(kNumBytesPerEntry);
ASSERT_OK(Put(Key(j * kNumFiles + i), value.c_str()));
}
ASSERT_OK(Flush());
}
ASSERT_OK(dbfull()->TEST_WaitForCompact());
ASSERT_EQ(0, NumTableFilesAtLevel(0));
ASSERT_EQ(kNumFiles, NumTableFilesAtLevel(1));
// Compression dictionary blocks are preloaded.
CheckCacheCountersForCompressionDict(
options, kNumFiles /* expected_compression_dict_misses */,
0 /* expected_compression_dict_hits */,
kNumFiles /* expected_compression_dict_inserts */);
// Seek to a key in a file. It should cause the SST's dictionary meta-block
// to be read.
RecordCacheCounters(options);
RecordCacheCountersForCompressionDict(options);
ReadOptions read_options;
ASSERT_NE("NOT_FOUND", Get(Key(kNumFiles * kNumEntriesPerFile - 1)));
// Two block hits: index and dictionary since they are prefetched
// One block missed/added: data block
CheckCacheCounters(options, 1 /* expected_misses */, 2 /* expected_hits */,
1 /* expected_inserts */, 0 /* expected_failures */);
CheckCacheCountersForCompressionDict(
options, 0 /* expected_compression_dict_misses */,
1 /* expected_compression_dict_hits */,
0 /* expected_compression_dict_inserts */);
}
}
static void ClearCache(Cache* cache) {
auto roles = CopyCacheDeleterRoleMap();
std::deque<std::string> keys;
Cache::ApplyToAllEntriesOptions opts;
auto callback = [&](const Slice& key, void* /*value*/, size_t /*charge*/,
Cache::DeleterFn deleter) {
if (roles.find(deleter) == roles.end()) {
// Keep the stats collector
return;
}
keys.push_back(key.ToString());
};
cache->ApplyToAllEntries(callback, opts);
for (auto& k : keys) {
cache->Erase(k);
}
}
TEST_F(DBBlockCacheTest, CacheEntryRoleStats) {
const size_t capacity = size_t{1} << 25;
int iterations_tested = 0;
for (bool partition : {false, true}) {
for (std::shared_ptr<Cache> cache : {NewLRUCache(capacity)}) {
// This test doesn't support FastLRUCache nor ClockCache because the
// keys used are not 16B long.
// TODO(guido) Add support for FastLRUCache and ClockCache.
if (!cache) {
// Skip clock cache when not supported
continue;
}
++iterations_tested;
Options options = CurrentOptions();
SetTimeElapseOnlySleepOnReopen(&options);
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.max_open_files = 13;
options.table_cache_numshardbits = 0;
// If this wakes up, it could interfere with test
options.stats_dump_period_sec = 0;
BlockBasedTableOptions table_options;
table_options.block_cache = cache;
table_options.cache_index_and_filter_blocks = true;
table_options.filter_policy.reset(NewBloomFilterPolicy(50));
if (partition) {
table_options.index_type = BlockBasedTableOptions::kTwoLevelIndexSearch;
table_options.partition_filters = true;
}
table_options.metadata_cache_options.top_level_index_pinning =
PinningTier::kNone;
table_options.metadata_cache_options.partition_pinning =
PinningTier::kNone;
table_options.metadata_cache_options.unpartitioned_pinning =
PinningTier::kNone;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
DestroyAndReopen(options);
// Create a new table.
ASSERT_OK(Put("foo", "value"));
ASSERT_OK(Put("bar", "value"));
ASSERT_OK(Flush());
ASSERT_OK(Put("zfoo", "value"));
ASSERT_OK(Put("zbar", "value"));
ASSERT_OK(Flush());
ASSERT_EQ(2, NumTableFilesAtLevel(0));
// Fresh cache
ClearCache(cache.get());
std::array<size_t, kNumCacheEntryRoles> expected{};
// For CacheEntryStatsCollector
expected[static_cast<size_t>(CacheEntryRole::kMisc)] = 1;
EXPECT_EQ(expected, GetCacheEntryRoleCountsBg());
std::array<size_t, kNumCacheEntryRoles> prev_expected = expected;
// First access only filters
ASSERT_EQ("NOT_FOUND", Get("different from any key added"));
expected[static_cast<size_t>(CacheEntryRole::kFilterBlock)] += 2;
if (partition) {
expected[static_cast<size_t>(CacheEntryRole::kFilterMetaBlock)] += 2;
}
// Within some time window, we will get cached entry stats
EXPECT_EQ(prev_expected, GetCacheEntryRoleCountsBg());
// Not enough to force a miss
env_->MockSleepForSeconds(45);
EXPECT_EQ(prev_expected, GetCacheEntryRoleCountsBg());
// Enough to force a miss
env_->MockSleepForSeconds(601);
EXPECT_EQ(expected, GetCacheEntryRoleCountsBg());
// Now access index and data block
ASSERT_EQ("value", Get("foo"));
expected[static_cast<size_t>(CacheEntryRole::kIndexBlock)]++;
if (partition) {
// top-level
expected[static_cast<size_t>(CacheEntryRole::kIndexBlock)]++;
}
expected[static_cast<size_t>(CacheEntryRole::kDataBlock)]++;
// Enough to force a miss
env_->MockSleepForSeconds(601);
// But inject a simulated long scan so that we need a longer
// interval to force a miss next time.
SyncPoint::GetInstance()->SetCallBack(
"CacheEntryStatsCollector::GetStats:AfterApplyToAllEntries",
[this](void*) {
// To spend no more than 0.2% of time scanning, we would need
// interval of at least 10000s
env_->MockSleepForSeconds(20);
});
SyncPoint::GetInstance()->EnableProcessing();
EXPECT_EQ(expected, GetCacheEntryRoleCountsBg());
prev_expected = expected;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
// The same for other file
ASSERT_EQ("value", Get("zfoo"));
expected[static_cast<size_t>(CacheEntryRole::kIndexBlock)]++;
if (partition) {
// top-level
expected[static_cast<size_t>(CacheEntryRole::kIndexBlock)]++;
}
expected[static_cast<size_t>(CacheEntryRole::kDataBlock)]++;
// Because of the simulated long scan, this is not enough to force
// a miss
env_->MockSleepForSeconds(601);
EXPECT_EQ(prev_expected, GetCacheEntryRoleCountsBg());
// But this is enough
env_->MockSleepForSeconds(10000);
EXPECT_EQ(expected, GetCacheEntryRoleCountsBg());
prev_expected = expected;
// Also check the GetProperty interface
std::map<std::string, std::string> values;
ASSERT_TRUE(
db_->GetMapProperty(DB::Properties::kBlockCacheEntryStats, &values));
for (size_t i = 0; i < kNumCacheEntryRoles; ++i) {
auto role = static_cast<CacheEntryRole>(i);
EXPECT_EQ(std::to_string(expected[i]),
values[BlockCacheEntryStatsMapKeys::EntryCount(role)]);
}
// Add one for kWriteBuffer
{
WriteBufferManager wbm(size_t{1} << 20, cache);
wbm.ReserveMem(1024);
expected[static_cast<size_t>(CacheEntryRole::kWriteBuffer)]++;
// Now we check that the GetProperty interface is more agressive about
// re-scanning stats, but not totally aggressive.
// Within some time window, we will get cached entry stats
env_->MockSleepForSeconds(1);
EXPECT_EQ(std::to_string(prev_expected[static_cast<size_t>(
CacheEntryRole::kWriteBuffer)]),
values[BlockCacheEntryStatsMapKeys::EntryCount(
CacheEntryRole::kWriteBuffer)]);
// Not enough for a "background" miss but enough for a "foreground" miss
env_->MockSleepForSeconds(45);
ASSERT_TRUE(db_->GetMapProperty(DB::Properties::kBlockCacheEntryStats,
&values));
EXPECT_EQ(
std::to_string(
expected[static_cast<size_t>(CacheEntryRole::kWriteBuffer)]),
values[BlockCacheEntryStatsMapKeys::EntryCount(
CacheEntryRole::kWriteBuffer)]);
}
prev_expected = expected;
// With collector pinned in cache, we should be able to hit
// even if the cache is full
ClearCache(cache.get());
Cache::Handle* h = nullptr;
ASSERT_OK(cache->Insert("Fill-it-up", nullptr, capacity + 1,
GetNoopDeleterForRole<CacheEntryRole::kMisc>(),
&h, Cache::Priority::HIGH));
ASSERT_GT(cache->GetUsage(), cache->GetCapacity());
expected = {};
// For CacheEntryStatsCollector
expected[static_cast<size_t>(CacheEntryRole::kMisc)] = 1;
// For Fill-it-up
expected[static_cast<size_t>(CacheEntryRole::kMisc)]++;
// Still able to hit on saved stats
EXPECT_EQ(prev_expected, GetCacheEntryRoleCountsBg());
// Enough to force a miss
env_->MockSleepForSeconds(1000);
EXPECT_EQ(expected, GetCacheEntryRoleCountsBg());
cache->Release(h);
// Now we test that the DB mutex is not held during scans, for the ways
// we know how to (possibly) trigger them. Without a better good way to
// check this, we simply inject an acquire & release of the DB mutex
// deep in the stat collection code. If we were already holding the
// mutex, that is UB that would at least be found by TSAN.
int scan_count = 0;
SyncPoint::GetInstance()->SetCallBack(
"CacheEntryStatsCollector::GetStats:AfterApplyToAllEntries",
[this, &scan_count](void*) {
dbfull()->TEST_LockMutex();
dbfull()->TEST_UnlockMutex();
++scan_count;
});
SyncPoint::GetInstance()->EnableProcessing();
// Different things that might trigger a scan, with mock sleeps to
// force a miss.
env_->MockSleepForSeconds(10000);
dbfull()->DumpStats();
ASSERT_EQ(scan_count, 1);
env_->MockSleepForSeconds(10000);
ASSERT_TRUE(
db_->GetMapProperty(DB::Properties::kBlockCacheEntryStats, &values));
ASSERT_EQ(scan_count, 2);
env_->MockSleepForSeconds(10000);
std::string value_str;
ASSERT_TRUE(
db_->GetProperty(DB::Properties::kBlockCacheEntryStats, &value_str));
ASSERT_EQ(scan_count, 3);
env_->MockSleepForSeconds(10000);
ASSERT_TRUE(db_->GetProperty(DB::Properties::kCFStats, &value_str));
// To match historical speed, querying this property no longer triggers
// a scan, even if results are old. But periodic dump stats should keep
// things reasonably updated.
ASSERT_EQ(scan_count, /*unchanged*/ 3);
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
}
EXPECT_GE(iterations_tested, 1);
}
}
#endif // ROCKSDB_LITE
class DBBlockCacheKeyTest
: public DBTestBase,
public testing::WithParamInterface<std::tuple<bool, bool>> {
public:
DBBlockCacheKeyTest()
: DBTestBase("db_block_cache_test", /*env_do_fsync=*/false) {}
void SetUp() override {
use_compressed_cache_ = std::get<0>(GetParam());
exclude_file_numbers_ = std::get<1>(GetParam());
}
bool use_compressed_cache_;
bool exclude_file_numbers_;
};
// Disable LinkFile so that we can physically copy a DB using Checkpoint.
// Disable file GetUniqueId to enable stable cache keys.
class StableCacheKeyTestFS : public FaultInjectionTestFS {
public:
explicit StableCacheKeyTestFS(const std::shared_ptr<FileSystem>& base)
: FaultInjectionTestFS(base) {
SetFailGetUniqueId(true);
}
virtual ~StableCacheKeyTestFS() override {}
IOStatus LinkFile(const std::string&, const std::string&, const IOOptions&,
IODebugContext*) override {
return IOStatus::NotSupported("Disabled");
}
};
TEST_P(DBBlockCacheKeyTest, StableCacheKeys) {
std::shared_ptr<StableCacheKeyTestFS> test_fs{
new StableCacheKeyTestFS(env_->GetFileSystem())};
std::unique_ptr<CompositeEnvWrapper> test_env{
new CompositeEnvWrapper(env_, test_fs)};
Options options = CurrentOptions();
options.create_if_missing = true;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
options.env = test_env.get();
BlockBasedTableOptions table_options;
int key_count = 0;
uint64_t expected_stat = 0;
std::function<void()> verify_stats;
if (use_compressed_cache_) {
if (!Snappy_Supported()) {
ROCKSDB_GTEST_SKIP("Compressed cache test requires snappy support");
return;
}
options.compression = CompressionType::kSnappyCompression;
table_options.no_block_cache = true;
table_options.block_cache_compressed = NewLRUCache(1 << 25, 0, false);
verify_stats = [&options, &expected_stat] {
// One for ordinary SST file and one for external SST file
ASSERT_EQ(expected_stat,
options.statistics->getTickerCount(BLOCK_CACHE_COMPRESSED_ADD));
};
} else {
table_options.cache_index_and_filter_blocks = true;
table_options.block_cache = NewLRUCache(1 << 25, 0, false);
verify_stats = [&options, &expected_stat] {
ASSERT_EQ(expected_stat,
options.statistics->getTickerCount(BLOCK_CACHE_DATA_ADD));
ASSERT_EQ(expected_stat,
options.statistics->getTickerCount(BLOCK_CACHE_INDEX_ADD));
ASSERT_EQ(expected_stat,
options.statistics->getTickerCount(BLOCK_CACHE_FILTER_ADD));
};
}
table_options.filter_policy.reset(NewBloomFilterPolicy(10, false));
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
CreateAndReopenWithCF({"koko"}, options);
if (exclude_file_numbers_) {
// Simulate something like old behavior without file numbers in properties.
// This is a "control" side of the test that also ensures safely degraded
// behavior on old files.
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"BlockBasedTableBuilder::BlockBasedTableBuilder:PreSetupBaseCacheKey",
[&](void* arg) {
TableProperties* props = reinterpret_cast<TableProperties*>(arg);
props->orig_file_number = 0;
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
}
std::function<void()> perform_gets = [&key_count, &expected_stat, this]() {
if (exclude_file_numbers_) {
// No cache key reuse should happen, because we can't rely on current
// file number being stable
expected_stat += key_count;
} else {
// Cache keys should be stable
expected_stat = key_count;
}
for (int i = 0; i < key_count; ++i) {
ASSERT_EQ(Get(1, Key(i)), "abc");
}
};
// Ordinary SST files with same session id
const std::string something_compressible(500U, 'x');
for (int i = 0; i < 2; ++i) {
ASSERT_OK(Put(1, Key(key_count), "abc"));
ASSERT_OK(Put(1, Key(key_count) + "a", something_compressible));
ASSERT_OK(Flush(1));
++key_count;
}
#ifndef ROCKSDB_LITE
// Save an export of those ordinary SST files for later
std::string export_files_dir = dbname_ + "/exported";
ExportImportFilesMetaData* metadata_ptr_ = nullptr;
Checkpoint* checkpoint;
ASSERT_OK(Checkpoint::Create(db_, &checkpoint));
ASSERT_OK(checkpoint->ExportColumnFamily(handles_[1], export_files_dir,
&metadata_ptr_));
ASSERT_NE(metadata_ptr_, nullptr);
delete checkpoint;
checkpoint = nullptr;
// External SST files with same session id
SstFileWriter sst_file_writer(EnvOptions(), options);
std::vector<std::string> external;
for (int i = 0; i < 2; ++i) {
std::string f = dbname_ + "/external" + std::to_string(i) + ".sst";
external.push_back(f);
ASSERT_OK(sst_file_writer.Open(f));
ASSERT_OK(sst_file_writer.Put(Key(key_count), "abc"));
ASSERT_OK(
sst_file_writer.Put(Key(key_count) + "a", something_compressible));
++key_count;
ExternalSstFileInfo external_info;
ASSERT_OK(sst_file_writer.Finish(&external_info));
IngestExternalFileOptions ingest_opts;
ASSERT_OK(db_->IngestExternalFile(handles_[1], {f}, ingest_opts));
}
if (exclude_file_numbers_) {
// FIXME(peterd): figure out where these extra ADDs are coming from
options.statistics->recordTick(BLOCK_CACHE_COMPRESSED_ADD,
uint64_t{0} - uint64_t{2});
}
#endif
perform_gets();
verify_stats();
// Make sure we can cache hit after re-open
ReopenWithColumnFamilies({"default", "koko"}, options);
perform_gets();
verify_stats();
// Make sure we can cache hit even on a full copy of the DB. Using
// StableCacheKeyTestFS, Checkpoint will resort to full copy not hard link.
// (Checkpoint not available in LITE mode to test this.)
#ifndef ROCKSDB_LITE
auto db_copy_name = dbname_ + "-copy";
ASSERT_OK(Checkpoint::Create(db_, &checkpoint));
ASSERT_OK(checkpoint->CreateCheckpoint(db_copy_name));
delete checkpoint;
Close();
Destroy(options);
// Switch to the DB copy
SaveAndRestore<std::string> save_dbname(&dbname_, db_copy_name);
ReopenWithColumnFamilies({"default", "koko"}, options);
perform_gets();
verify_stats();
// And ensure that re-importing + ingesting the same files into a
// different DB uses same cache keys
DestroyAndReopen(options);
ColumnFamilyHandle* cfh = nullptr;
ASSERT_OK(db_->CreateColumnFamilyWithImport(ColumnFamilyOptions(), "yoyo",
ImportColumnFamilyOptions(),
*metadata_ptr_, &cfh));
ASSERT_NE(cfh, nullptr);
delete cfh;
cfh = nullptr;
delete metadata_ptr_;
metadata_ptr_ = nullptr;
DestroyDB(export_files_dir, options);
ReopenWithColumnFamilies({"default", "yoyo"}, options);
IngestExternalFileOptions ingest_opts;
ASSERT_OK(db_->IngestExternalFile(handles_[1], {external}, ingest_opts));
perform_gets();
verify_stats();
#endif // !ROCKSDB_LITE
Close();
Destroy(options);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
class CacheKeyTest : public testing::Test {
public:
void SetupStableBase() {
// Like SemiStructuredUniqueIdGen::GenerateNext
tp_.db_session_id = EncodeSessionId(base_session_upper_,
base_session_lower_ ^ session_counter_);
tp_.db_id = std::to_string(db_id_);
tp_.orig_file_number = file_number_;
bool is_stable;
std::string cur_session_id = ""; // ignored
uint64_t cur_file_number = 42; // ignored
BlockBasedTable::SetupBaseCacheKey(&tp_, cur_session_id, cur_file_number,
file_size_, &base_cache_key_,
&is_stable);
ASSERT_TRUE(is_stable);
}
CacheKey WithOffset(uint64_t offset) {
return BlockBasedTable::GetCacheKey(base_cache_key_,
BlockHandle(offset, /*size*/ 5));
}
protected:
OffsetableCacheKey base_cache_key_;
TableProperties tp_;
uint64_t file_size_ = 0;
uint64_t base_session_upper_ = 0;
uint64_t base_session_lower_ = 0;
uint64_t session_counter_ = 0;
uint64_t file_number_ = 0;
uint64_t db_id_ = 0;
};
namespace {
template <typename T>
int CountBitsDifferent(const T& t1, const T& t2) {
int diff = 0;
const uint8_t* p1 = reinterpret_cast<const uint8_t*>(&t1);
const uint8_t* p2 = reinterpret_cast<const uint8_t*>(&t2);
static_assert(sizeof(*p1) == 1, "Expecting uint8_t byte");
for (size_t i = 0; i < sizeof(T); ++i) {
diff += BitsSetToOne(p1[i] ^ p2[i]);
}
return diff;
}
} // namespace
TEST_F(CacheKeyTest, DBImplSessionIdStructure) {
// We have to generate our own session IDs for simulation purposes in other
// tests. Here we verify that the DBImpl implementation seems to match
// our construction here, by using lowest XORed-in bits for "session
// counter."
std::string session_id1 = DBImpl::GenerateDbSessionId(/*env*/ nullptr);
std::string session_id2 = DBImpl::GenerateDbSessionId(/*env*/ nullptr);
uint64_t upper1, upper2, lower1, lower2;
ASSERT_OK(DecodeSessionId(session_id1, &upper1, &lower1));
ASSERT_OK(DecodeSessionId(session_id2, &upper2, &lower2));
// Because generated in same process
ASSERT_EQ(upper1, upper2);
// Unless we generate > 4 billion session IDs in this process...
ASSERT_EQ(Upper32of64(lower1), Upper32of64(lower2));
// But they must be different somewhere
ASSERT_NE(Lower32of64(lower1), Lower32of64(lower2));
}
TEST_F(CacheKeyTest, StandardEncodingLimit) {
base_session_upper_ = 1234;
base_session_lower_ = 5678;
session_counter_ = 42;
file_number_ = 42;
db_id_ = 1234;
file_size_ = 42;
SetupStableBase();
CacheKey ck1;
ASSERT_TRUE(ck1.IsEmpty());
ck1 = WithOffset(0);
ASSERT_FALSE(ck1.IsEmpty());
// Should use same encoding
file_size_ = BlockBasedTable::kMaxFileSizeStandardEncoding;
SetupStableBase();
CacheKey ck2 = WithOffset(0);
ASSERT_EQ(CountBitsDifferent(ck1, ck2), 0);
// Should use different encoding
++file_size_;
SetupStableBase();
CacheKey ck3 = WithOffset(0);
ASSERT_GT(CountBitsDifferent(ck2, ck3), 0);
}
TEST_F(CacheKeyTest, Encodings) {
// Claim from cache_key.cc:
// In fact, if our SST files are all < 4TB (see
// BlockBasedTable::kMaxFileSizeStandardEncoding), then SST files generated
// in a single process are guaranteed to have unique cache keys, unless/until
// number session ids * max file number = 2**86, e.g. 1 trillion DB::Open in
// a single process and 64 trillion files generated.
// We can generalize that. For
// * z bits in maximum file size
// * n bits in maximum file number
// * s bits in maximum session counter
// uniqueness is guaranteed at least when all of these hold:
// * z + n + s <= 121 (128 - 2 meta + 2 offset trim - (8-1) byte granularity
// in encoding)
// * n + s <= 86 (encoding limitation)
// * s <= 62 (because of 2-bit metadata)
// We can verify this indirectly by how input bits get into the cache key,
// but we have to be mindful that for sufficiently large file sizes,
// different encodings might be used. But for cases mixing large and small
// files, we have to verify uniqueness between encodings.
// Going through all combinations would be a little expensive, so we test
// only one random "stripe" of the configuration space per run.
constexpr uint32_t kStripeBits = 8;
constexpr uint32_t kStripeMask = (uint32_t{1} << kStripeBits) - 1;
// Also cycle through stripes on repeated runs (not thread safe)
static uint32_t stripe =
static_cast<uint32_t>(std::random_device{}()) & kStripeMask;
stripe = (stripe + 1) & kStripeMask;
fprintf(stderr, "%u\n", stripe);
// We are going to randomly initialize some values which *should* not affect
// result
Random64 r{std::random_device{}()};
int max_num_encodings = 0;
uint32_t config_num = 0;
uint32_t session_counter_bits, file_number_bits, max_file_size_bits;
// Inner loop body, used later in a loop over configurations
auto TestConfig = [&]() {
base_session_upper_ = r.Next();
base_session_lower_ = r.Next();
session_counter_ = r.Next();
if (session_counter_bits < 64) {
// Avoid shifting UB
session_counter_ = session_counter_ >> 1 >> (63 - session_counter_bits);
}
file_number_ = r.Next() >> (64 - file_number_bits);
// Need two bits set to avoid temporary zero below
if (BitsSetToOne(file_number_) < 2) {
file_number_ = 3;
}
db_id_ = r.Next();
// Work-around clang-analyzer which thinks empty last_base is garbage
CacheKey last_base = CacheKey::CreateUniqueForProcessLifetime();
std::unordered_set<std::string> seen;
int num_encodings = 0;
// Loop over encodings by increasing file size bits
for (uint32_t file_size_bits = 1; file_size_bits <= max_file_size_bits;
++file_size_bits) {
file_size_ = uint64_t{1} << (file_size_bits - 1);
SetupStableBase();
CacheKey new_base = WithOffset(0);
if (CountBitsDifferent(last_base, new_base) == 0) {
// Same as previous encoding
continue;
}
// New encoding
++num_encodings;
ASSERT_TRUE(seen.insert(new_base.AsSlice().ToString()).second);
last_base = new_base;
for (uint32_t i = 0; i < file_size_bits; ++i) {
CacheKey ck = WithOffset(uint64_t{1} << i);
if (i < 2) {
// These cases are not relevant and optimized by dropping two
// lowest bits because there's always at least 5 bytes between
// blocks.
ASSERT_EQ(CountBitsDifferent(ck, new_base), 0);
} else {
// Normal case
// 1 bit different from base and never been seen implies the bit
// is encoded into cache key without overlapping other structured
// data.
ASSERT_EQ(CountBitsDifferent(ck, new_base), 1);
ASSERT_TRUE(seen.insert(ck.AsSlice().ToString()).second);
}
}
for (uint32_t i = 0; i < session_counter_bits; ++i) {
SaveAndRestore<uint64_t> tmp(&session_counter_,
session_counter_ ^ (uint64_t{1} << i));
SetupStableBase();
CacheKey ck = WithOffset(0);
ASSERT_EQ(CountBitsDifferent(ck, new_base), 1);
ASSERT_TRUE(seen.insert(ck.AsSlice().ToString()).second);
}
for (uint32_t i = 0; i < file_number_bits; ++i) {
SaveAndRestore<uint64_t> tmp(&file_number_,
file_number_ ^ (uint64_t{1} << i));
SetupStableBase();
CacheKey ck = WithOffset(0);
ASSERT_EQ(CountBitsDifferent(ck, new_base), 1);
ASSERT_TRUE(seen.insert(ck.AsSlice().ToString()).second);
}
max_num_encodings = std::max(max_num_encodings, num_encodings);
}
};
// Loop over configurations and test those in stripe
for (session_counter_bits = 0; session_counter_bits <= 62;
++session_counter_bits) {
uint32_t max_file_number_bits =
std::min(uint32_t{64}, uint32_t{86} - session_counter_bits);
// Start with 2 to avoid file_number_ == 0 in testing
for (file_number_bits = 2; file_number_bits <= max_file_number_bits;
++file_number_bits) {
uint32_t max_max_file_size_bits =
std::min(uint32_t{64},
uint32_t{121} - file_number_bits - session_counter_bits);
for (max_file_size_bits = 1; max_file_size_bits <= max_max_file_size_bits;
++max_file_size_bits) {
if ((config_num++ & kStripeMask) == stripe) {
TestConfig();
}
}
}
}
// Make sure the current implementation is exercised
ASSERT_EQ(max_num_encodings, 4);
}
INSTANTIATE_TEST_CASE_P(DBBlockCacheKeyTest, DBBlockCacheKeyTest,
::testing::Combine(::testing::Bool(),
::testing::Bool()));
class DBBlockCachePinningTest
: public DBTestBase,
public testing::WithParamInterface<
std::tuple<bool, PinningTier, PinningTier, PinningTier>> {
public:
DBBlockCachePinningTest()
: DBTestBase("db_block_cache_test", /*env_do_fsync=*/false) {}
void SetUp() override {
partition_index_and_filters_ = std::get<0>(GetParam());
top_level_index_pinning_ = std::get<1>(GetParam());
partition_pinning_ = std::get<2>(GetParam());
unpartitioned_pinning_ = std::get<3>(GetParam());
}
bool partition_index_and_filters_;
PinningTier top_level_index_pinning_;
PinningTier partition_pinning_;
PinningTier unpartitioned_pinning_;
};
TEST_P(DBBlockCachePinningTest, TwoLevelDB) {
// Creates one file in L0 and one file in L1. Both files have enough data that
// their index and filter blocks are partitioned. The L1 file will also have
// a compression dictionary (those are trained only during compaction), which
// must be unpartitioned.
const int kKeySize = 32;
const int kBlockSize = 128;
const int kNumBlocksPerFile = 128;
const int kNumKeysPerFile = kBlockSize * kNumBlocksPerFile / kKeySize;
Options options = CurrentOptions();
// `kNoCompression` makes the unit test more portable. But it relies on the
// current behavior of persisting/accessing dictionary even when there's no
// (de)compression happening, which seems fairly likely to change over time.
options.compression = kNoCompression;
options.compression_opts.max_dict_bytes = 4 << 10;
options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.block_cache = NewLRUCache(1 << 20 /* capacity */);
table_options.block_size = kBlockSize;
table_options.metadata_block_size = kBlockSize;
table_options.cache_index_and_filter_blocks = true;
table_options.metadata_cache_options.top_level_index_pinning =
top_level_index_pinning_;
table_options.metadata_cache_options.partition_pinning = partition_pinning_;
table_options.metadata_cache_options.unpartitioned_pinning =
unpartitioned_pinning_;
table_options.filter_policy.reset(
NewBloomFilterPolicy(10 /* bits_per_key */));
if (partition_index_and_filters_) {
table_options.index_type =
BlockBasedTableOptions::IndexType::kTwoLevelIndexSearch;
table_options.partition_filters = true;
}
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
Reopen(options);
Random rnd(301);
for (int i = 0; i < 2; ++i) {
for (int j = 0; j < kNumKeysPerFile; ++j) {
ASSERT_OK(Put(Key(i * kNumKeysPerFile + j), rnd.RandomString(kKeySize)));
}
ASSERT_OK(Flush());
if (i == 0) {
// Prevent trivial move so file will be rewritten with dictionary and
// reopened with L1's pinning settings.
CompactRangeOptions cro;
cro.bottommost_level_compaction = BottommostLevelCompaction::kForce;
ASSERT_OK(db_->CompactRange(cro, nullptr, nullptr));
}
}
// Clear all unpinned blocks so unpinned blocks will show up as cache misses
// when reading a key from a file.
table_options.block_cache->EraseUnRefEntries();
// Get base cache values
uint64_t filter_misses = TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS);
uint64_t index_misses = TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS);
uint64_t compression_dict_misses =
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_MISS);
// Read a key from the L0 file
Get(Key(kNumKeysPerFile));
uint64_t expected_filter_misses = filter_misses;
uint64_t expected_index_misses = index_misses;
uint64_t expected_compression_dict_misses = compression_dict_misses;
if (partition_index_and_filters_) {
if (top_level_index_pinning_ == PinningTier::kNone) {
++expected_filter_misses;
++expected_index_misses;
}
if (partition_pinning_ == PinningTier::kNone) {
++expected_filter_misses;
++expected_index_misses;
}
} else {
if (unpartitioned_pinning_ == PinningTier::kNone) {
++expected_filter_misses;
++expected_index_misses;
}
}
if (unpartitioned_pinning_ == PinningTier::kNone) {
++expected_compression_dict_misses;
}
ASSERT_EQ(expected_filter_misses,
TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(expected_index_misses,
TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(expected_compression_dict_misses,
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_MISS));
// Clear all unpinned blocks so unpinned blocks will show up as cache misses
// when reading a key from a file.
table_options.block_cache->EraseUnRefEntries();
// Read a key from the L1 file
Get(Key(0));
if (partition_index_and_filters_) {
if (top_level_index_pinning_ == PinningTier::kNone ||
top_level_index_pinning_ == PinningTier::kFlushedAndSimilar) {
++expected_filter_misses;
++expected_index_misses;
}
if (partition_pinning_ == PinningTier::kNone ||
partition_pinning_ == PinningTier::kFlushedAndSimilar) {
++expected_filter_misses;
++expected_index_misses;
}
} else {
if (unpartitioned_pinning_ == PinningTier::kNone ||
unpartitioned_pinning_ == PinningTier::kFlushedAndSimilar) {
++expected_filter_misses;
++expected_index_misses;
}
}
if (unpartitioned_pinning_ == PinningTier::kNone ||
unpartitioned_pinning_ == PinningTier::kFlushedAndSimilar) {
++expected_compression_dict_misses;
}
ASSERT_EQ(expected_filter_misses,
TestGetTickerCount(options, BLOCK_CACHE_FILTER_MISS));
ASSERT_EQ(expected_index_misses,
TestGetTickerCount(options, BLOCK_CACHE_INDEX_MISS));
ASSERT_EQ(expected_compression_dict_misses,
TestGetTickerCount(options, BLOCK_CACHE_COMPRESSION_DICT_MISS));
}
INSTANTIATE_TEST_CASE_P(
DBBlockCachePinningTest, DBBlockCachePinningTest,
::testing::Combine(
::testing::Bool(),
::testing::Values(PinningTier::kNone, PinningTier::kFlushedAndSimilar,
PinningTier::kAll),
::testing::Values(PinningTier::kNone, PinningTier::kFlushedAndSimilar,
PinningTier::kAll),
::testing::Values(PinningTier::kNone, PinningTier::kFlushedAndSimilar,
PinningTier::kAll)));
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}