rocksdb/memtable/write_buffer_manager_test.cc
mrambacher 12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead.  There are likely more places that can be changed, but this is a start to show what can/should be done.  Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.

There are several Env classes that implement these functions.  Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR.  It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).

Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00

205 lines
7.8 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 "rocksdb/write_buffer_manager.h"
#include "test_util/testharness.h"
namespace ROCKSDB_NAMESPACE {
class WriteBufferManagerTest : public testing::Test {};
#ifndef ROCKSDB_LITE
const size_t kSizeDummyEntry = 256 * 1024;
TEST_F(WriteBufferManagerTest, ShouldFlush) {
// A write buffer manager of size 10MB
std::unique_ptr<WriteBufferManager> wbf(
new WriteBufferManager(10 * 1024 * 1024));
wbf->ReserveMem(8 * 1024 * 1024);
ASSERT_FALSE(wbf->ShouldFlush());
// 90% of the hard limit will hit the condition
wbf->ReserveMem(1 * 1024 * 1024);
ASSERT_TRUE(wbf->ShouldFlush());
// Scheduling for freeing will release the condition
wbf->ScheduleFreeMem(1 * 1024 * 1024);
ASSERT_FALSE(wbf->ShouldFlush());
wbf->ReserveMem(2 * 1024 * 1024);
ASSERT_TRUE(wbf->ShouldFlush());
wbf->ScheduleFreeMem(4 * 1024 * 1024);
// 11MB total, 6MB mutable. hard limit still hit
ASSERT_TRUE(wbf->ShouldFlush());
wbf->ScheduleFreeMem(2 * 1024 * 1024);
// 11MB total, 4MB mutable. hard limit stills but won't flush because more
// than half data is already being flushed.
ASSERT_FALSE(wbf->ShouldFlush());
wbf->ReserveMem(4 * 1024 * 1024);
// 15 MB total, 8MB mutable.
ASSERT_TRUE(wbf->ShouldFlush());
wbf->FreeMem(7 * 1024 * 1024);
// 9MB total, 8MB mutable.
ASSERT_FALSE(wbf->ShouldFlush());
}
TEST_F(WriteBufferManagerTest, CacheCost) {
LRUCacheOptions co;
// 1GB cache
co.capacity = 1024 * 1024 * 1024;
co.num_shard_bits = 4;
co.metadata_charge_policy = kDontChargeCacheMetadata;
std::shared_ptr<Cache> cache = NewLRUCache(co);
// A write buffer manager of size 50MB
std::unique_ptr<WriteBufferManager> wbf(
new WriteBufferManager(50 * 1024 * 1024, cache));
// Allocate 333KB will allocate 512KB
wbf->ReserveMem(333 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 2 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 2 * 256 * 1024 + 10000);
// 2 dummy entries are added for size 333 kb.
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 2 * kSizeDummyEntry);
// Allocate another 512KB
wbf->ReserveMem(512 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 4 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 4 * 256 * 1024 + 10000);
// 2 more dummy entries are added for size 512.
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 4 * kSizeDummyEntry);
// Allocate another 10MB
wbf->ReserveMem(10 * 1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 11 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 11 * 1024 * 1024 + 10000);
// 40 more entries are added for size 10 * 1024 * 1024.
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 44 * kSizeDummyEntry);
// Free 1MB will not cause any change in cache cost
wbf->FreeMem(1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 11 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 11 * 1024 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 44 * kSizeDummyEntry);
ASSERT_FALSE(wbf->ShouldFlush());
// Allocate another 41MB
wbf->ReserveMem(41 * 1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 204 * kSizeDummyEntry);
ASSERT_TRUE(wbf->ShouldFlush());
ASSERT_TRUE(wbf->ShouldFlush());
wbf->ScheduleFreeMem(20 * 1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 204 * kSizeDummyEntry);
// Still need flush as the hard limit hits
ASSERT_TRUE(wbf->ShouldFlush());
// Free 20MB will releae 256KB from cache
wbf->FreeMem(20 * 1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 256 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 203 * kSizeDummyEntry);
ASSERT_FALSE(wbf->ShouldFlush());
// Every free will release 256KB if still not hit 3/4
wbf->FreeMem(16 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 2 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 2 * 256 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 202 * kSizeDummyEntry);
wbf->FreeMem(16 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 3 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 3 * 256 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 201 * kSizeDummyEntry);
// Reserve 512KB will not cause any change in cache cost
wbf->ReserveMem(512 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 3 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 3 * 256 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 201 * kSizeDummyEntry);
wbf->FreeMem(16 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 4 * 256 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 51 * 1024 * 1024 - 4 * 256 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 200 * kSizeDummyEntry);
// Destory write buffer manger should free everything
wbf.reset();
ASSERT_LT(cache->GetPinnedUsage(), 1024 * 1024);
}
TEST_F(WriteBufferManagerTest, NoCapCacheCost) {
// 1GB cache
std::shared_ptr<Cache> cache = NewLRUCache(1024 * 1024 * 1024, 4);
// A write buffer manager of size 256MB
std::unique_ptr<WriteBufferManager> wbf(new WriteBufferManager(0, cache));
// Allocate 1.5MB will allocate 2MB
wbf->ReserveMem(10 * 1024 * 1024);
ASSERT_GE(cache->GetPinnedUsage(), 10 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 10 * 1024 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 40 * kSizeDummyEntry);
ASSERT_FALSE(wbf->ShouldFlush());
wbf->FreeMem(9 * 1024 * 1024);
for (int i = 0; i < 40; i++) {
wbf->FreeMem(4 * 1024);
}
ASSERT_GE(cache->GetPinnedUsage(), 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 1024 * 1024 + 10000);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 4 * kSizeDummyEntry);
}
TEST_F(WriteBufferManagerTest, CacheFull) {
// 15MB cache size with strict capacity
LRUCacheOptions lo;
lo.capacity = 12 * 1024 * 1024;
lo.num_shard_bits = 0;
lo.strict_capacity_limit = true;
std::shared_ptr<Cache> cache = NewLRUCache(lo);
std::unique_ptr<WriteBufferManager> wbf(new WriteBufferManager(0, cache));
wbf->ReserveMem(10 * 1024 * 1024);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 40 * kSizeDummyEntry);
size_t prev_pinned = cache->GetPinnedUsage();
ASSERT_GE(prev_pinned, 10 * 1024 * 1024);
// Some insert will fail
wbf->ReserveMem(10 * 1024 * 1024);
ASSERT_LE(cache->GetPinnedUsage(), 12 * 1024 * 1024);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 80 * kSizeDummyEntry);
// Increase capacity so next insert will succeed
cache->SetCapacity(30 * 1024 * 1024);
wbf->ReserveMem(10 * 1024 * 1024);
ASSERT_GT(cache->GetPinnedUsage(), 20 * 1024 * 1024);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 120 * kSizeDummyEntry);
// Gradually release 20 MB
for (int i = 0; i < 40; i++) {
wbf->FreeMem(512 * 1024);
}
ASSERT_GE(cache->GetPinnedUsage(), 10 * 1024 * 1024);
ASSERT_LT(cache->GetPinnedUsage(), 20 * 1024 * 1024);
ASSERT_EQ(wbf->dummy_entries_in_cache_usage(), 95 * kSizeDummyEntry);
}
#endif // ROCKSDB_LITE
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}