rocksdb/db/db_write_buffer_manager_test.cc
Changyu Bi 76ed9a3990 Add missing status check when compiling with ASSERT_STATUS_CHECKED=1 (#11686)
Summary:
It seems the flag `-fno-elide-constructors` is incorrectly overwritten in Makefile by 9c2ebcc2c3/Makefile (L243)
Applying the change in PR https://github.com/facebook/rocksdb/issues/11675 shows a lot of missing status checks. This PR adds the missing status checks.

Most of changes are just adding asserts in unit tests. I'll add pr comment around more interesting changes that need review.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11686

Test Plan: change Makefile as in https://github.com/facebook/rocksdb/issues/11675, and run `ASSERT_STATUS_CHECKED=1 TEST_UINT128_COMPAT=1 ROCKSDB_MODIFY_NPHASH=1 LIB_MODE=static OPT="-DROCKSDB_NAMESPACE=alternative_rocksdb_ns" make V=1 -j24 J=24 check`

Reviewed By: hx235

Differential Revision: D48176132

Pulled By: cbi42

fbshipit-source-id: 6758946cfb1c6ff84c4c1e0ca540d05e6fc390bd
2023-08-09 15:46:44 -07:00

928 lines
32 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 "db/db_test_util.h"
#include "db/write_thread.h"
#include "port/stack_trace.h"
namespace ROCKSDB_NAMESPACE {
class DBWriteBufferManagerTest : public DBTestBase,
public testing::WithParamInterface<bool> {
public:
DBWriteBufferManagerTest()
: DBTestBase("db_write_buffer_manager_test", /*env_do_fsync=*/false) {}
bool cost_cache_;
};
TEST_P(DBWriteBufferManagerTest, SharedBufferAcrossCFs1) {
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
WriteOptions wo;
wo.disableWAL = true;
CreateAndReopenWithCF({"cf1", "cf2", "cf3"}, options);
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(3));
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Put(0, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(0));
// Write to "Default", "cf2" and "cf3".
ASSERT_OK(Put(3, Key(1), DummyString(30000), wo));
ASSERT_OK(Put(0, Key(1), DummyString(40000), wo));
ASSERT_OK(Put(2, Key(1), DummyString(1), wo));
ASSERT_OK(Put(3, Key(2), DummyString(40000), wo));
// WriteBufferManager::buffer_size_ has exceeded after the previous write is
// completed.
// This make sures write will go through and if stall was in effect, it will
// end.
ASSERT_OK(Put(0, Key(2), DummyString(1), wo));
}
// Test Single DB with multiple writer threads get blocked when
// WriteBufferManager execeeds buffer_size_ and flush is waiting to be
// finished.
TEST_P(DBWriteBufferManagerTest, SharedWriteBufferAcrossCFs2) {
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
WriteOptions wo;
wo.disableWAL = true;
CreateAndReopenWithCF({"cf1", "cf2", "cf3"}, options);
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(3));
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Put(0, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(0));
// Write to "Default", "cf2" and "cf3". No flush will be triggered.
ASSERT_OK(Put(3, Key(1), DummyString(30000), wo));
ASSERT_OK(Put(0, Key(1), DummyString(40000), wo));
ASSERT_OK(Put(2, Key(1), DummyString(1), wo));
ASSERT_OK(Put(3, Key(2), DummyString(40000), wo));
// WriteBufferManager::buffer_size_ has exceeded after the previous write is
// completed.
std::unordered_set<WriteThread::Writer*> w_set;
std::vector<port::Thread> threads;
int wait_count_db = 0;
int num_writers = 4;
InstrumentedMutex mutex;
InstrumentedCondVar cv(&mutex);
std::atomic<int> thread_num(0);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0",
"DBImpl::BackgroundCallFlush:start"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WBMStallInterface::BlockDB", [&](void*) {
InstrumentedMutexLock lock(&mutex);
wait_count_db++;
cv.SignalAll();
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WriteThread::WriteStall::Wait", [&](void* arg) {
InstrumentedMutexLock lock(&mutex);
WriteThread::Writer* w = reinterpret_cast<WriteThread::Writer*>(arg);
w_set.insert(w);
// Allow the flush to continue if all writer threads are blocked.
if (w_set.size() == (unsigned long)num_writers) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
bool s = true;
std::function<void(int)> writer = [&](int cf) {
int a = thread_num.fetch_add(1);
std::string key = "foo" + std::to_string(a);
Status tmp = Put(cf, Slice(key), DummyString(1), wo);
InstrumentedMutexLock lock(&mutex);
s = s && tmp.ok();
};
// Flow:
// main_writer thread will write but will be blocked (as Flush will on hold,
// buffer_size_ has exceeded, thus will create stall in effect).
// |
// |
// multiple writer threads will be created to write across multiple columns
// and they will be blocked.
// |
// |
// Last writer thread will write and when its blocked it will signal Flush to
// continue to clear the stall.
threads.emplace_back(writer, 1);
// Wait untill first thread (main_writer) writing to DB is blocked and then
// create the multiple writers which will be blocked from getting added to the
// queue because stall is in effect.
{
InstrumentedMutexLock lock(&mutex);
while (wait_count_db != 1) {
cv.Wait();
}
}
for (int i = 0; i < num_writers; i++) {
threads.emplace_back(writer, i % 4);
}
for (auto& t : threads) {
t.join();
}
ASSERT_TRUE(s);
// Number of DBs blocked.
ASSERT_EQ(wait_count_db, 1);
// Number of Writer threads blocked.
ASSERT_EQ(w_set.size(), num_writers);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Test multiple DBs get blocked when WriteBufferManager limit exceeds and flush
// is waiting to be finished but DBs tries to write meanwhile.
TEST_P(DBWriteBufferManagerTest, SharedWriteBufferLimitAcrossDB) {
std::vector<std::string> dbnames;
std::vector<DB*> dbs;
int num_dbs = 3;
for (int i = 0; i < num_dbs; i++) {
dbs.push_back(nullptr);
dbnames.push_back(
test::PerThreadDBPath("db_shared_wb_db" + std::to_string(i)));
}
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
CreateAndReopenWithCF({"cf1", "cf2"}, options);
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(DestroyDB(dbnames[i], options));
ASSERT_OK(DB::Open(options, dbnames[i], &(dbs[i])));
}
WriteOptions wo;
wo.disableWAL = true;
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Put(wo, Key(1), DummyString(20000)));
}
// Insert to db_.
ASSERT_OK(Put(0, Key(1), DummyString(30000), wo));
// WriteBufferManager Limit exceeded.
std::vector<port::Thread> threads;
int wait_count_db = 0;
InstrumentedMutex mutex;
InstrumentedCondVar cv(&mutex);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0",
"DBImpl::BackgroundCallFlush:start"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WBMStallInterface::BlockDB", [&](void*) {
{
InstrumentedMutexLock lock(&mutex);
wait_count_db++;
cv.Signal();
// Since this is the last DB, signal Flush to continue.
if (wait_count_db == num_dbs + 1) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
bool s = true;
// Write to DB.
std::function<void(DB*)> write_db = [&](DB* db) {
Status tmp = db->Put(wo, Key(3), DummyString(1));
InstrumentedMutexLock lock(&mutex);
s = s && tmp.ok();
};
// Flow:
// db_ will write and will be blocked (as Flush will on hold and will create
// stall in effect).
// |
// multiple dbs writers will be created to write to that db and they will be
// blocked.
// |
// |
// Last writer will write and when its blocked it will signal Flush to
// continue to clear the stall.
threads.emplace_back(write_db, db_);
// Wait untill first DB is blocked and then create the multiple writers for
// different DBs which will be blocked from getting added to the queue because
// stall is in effect.
{
InstrumentedMutexLock lock(&mutex);
while (wait_count_db != 1) {
cv.Wait();
}
}
for (int i = 0; i < num_dbs; i++) {
threads.emplace_back(write_db, dbs[i]);
}
for (auto& t : threads) {
t.join();
}
ASSERT_TRUE(s);
ASSERT_EQ(num_dbs + 1, wait_count_db);
// Clean up DBs.
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Close());
ASSERT_OK(DestroyDB(dbnames[i], options));
delete dbs[i];
}
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Test multiple threads writing across multiple DBs and multiple columns get
// blocked when stall by WriteBufferManager is in effect.
TEST_P(DBWriteBufferManagerTest, SharedWriteBufferLimitAcrossDB1) {
std::vector<std::string> dbnames;
std::vector<DB*> dbs;
int num_dbs = 3;
for (int i = 0; i < num_dbs; i++) {
dbs.push_back(nullptr);
dbnames.push_back(
test::PerThreadDBPath("db_shared_wb_db" + std::to_string(i)));
}
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
CreateAndReopenWithCF({"cf1", "cf2"}, options);
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(DestroyDB(dbnames[i], options));
ASSERT_OK(DB::Open(options, dbnames[i], &(dbs[i])));
}
WriteOptions wo;
wo.disableWAL = true;
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Put(wo, Key(1), DummyString(20000)));
}
// Insert to db_.
ASSERT_OK(Put(0, Key(1), DummyString(30000), wo));
// WriteBufferManager::buffer_size_ has exceeded after the previous write to
// dbs[0] is completed.
std::vector<port::Thread> threads;
int wait_count_db = 0;
InstrumentedMutex mutex;
InstrumentedCondVar cv(&mutex);
std::unordered_set<WriteThread::Writer*> w_set;
std::vector<port::Thread> writer_threads;
std::atomic<int> thread_num(0);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0",
"DBImpl::BackgroundCallFlush:start"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WBMStallInterface::BlockDB", [&](void*) {
{
InstrumentedMutexLock lock(&mutex);
wait_count_db++;
thread_num.fetch_add(1);
cv.Signal();
// Allow the flush to continue if all writer threads are blocked.
if (thread_num.load(std::memory_order_relaxed) == 2 * num_dbs + 1) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WriteThread::WriteStall::Wait", [&](void* arg) {
WriteThread::Writer* w = reinterpret_cast<WriteThread::Writer*>(arg);
{
InstrumentedMutexLock lock(&mutex);
w_set.insert(w);
thread_num.fetch_add(1);
// Allow the flush continue if all writer threads are blocked.
if (thread_num.load(std::memory_order_relaxed) == 2 * num_dbs + 1) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
bool s1 = true, s2 = true;
// Write to multiple columns of db_.
std::function<void(int)> write_cf = [&](int cf) {
Status tmp = Put(cf, Key(3), DummyString(1), wo);
InstrumentedMutexLock lock(&mutex);
s1 = s1 && tmp.ok();
};
// Write to multiple DBs.
std::function<void(DB*)> write_db = [&](DB* db) {
Status tmp = db->Put(wo, Key(3), DummyString(1));
InstrumentedMutexLock lock(&mutex);
s2 = s2 && tmp.ok();
};
// Flow:
// thread will write to db_ will be blocked (as Flush will on hold,
// buffer_size_ has exceeded and will create stall in effect).
// |
// |
// multiple writers threads writing to different DBs and to db_ across
// multiple columns will be created and they will be blocked due to stall.
// |
// |
// Last writer thread will write and when its blocked it will signal Flush to
// continue to clear the stall.
threads.emplace_back(write_db, db_);
// Wait untill first thread is blocked and then create the multiple writer
// threads.
{
InstrumentedMutexLock lock(&mutex);
while (wait_count_db != 1) {
cv.Wait();
}
}
for (int i = 0; i < num_dbs; i++) {
// Write to multiple columns of db_.
writer_threads.emplace_back(write_cf, i % 3);
// Write to different dbs.
threads.emplace_back(write_db, dbs[i]);
}
for (auto& t : threads) {
t.join();
}
for (auto& t : writer_threads) {
t.join();
}
ASSERT_TRUE(s1);
ASSERT_TRUE(s2);
// Number of DBs blocked.
ASSERT_EQ(num_dbs + 1, wait_count_db);
// Number of Writer threads blocked.
ASSERT_EQ(w_set.size(), num_dbs);
// Clean up DBs.
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Close());
ASSERT_OK(DestroyDB(dbnames[i], options));
delete dbs[i];
}
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Test multiple threads writing across multiple columns of db_ by passing
// different values to WriteOption.no_slown_down.
TEST_P(DBWriteBufferManagerTest, MixedSlowDownOptionsSingleDB) {
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
WriteOptions wo;
wo.disableWAL = true;
CreateAndReopenWithCF({"cf1", "cf2", "cf3"}, options);
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(3));
ASSERT_OK(Put(3, Key(1), DummyString(1), wo));
ASSERT_OK(Put(0, Key(1), DummyString(1), wo));
ASSERT_OK(Flush(0));
// Write to "Default", "cf2" and "cf3". No flush will be triggered.
ASSERT_OK(Put(3, Key(1), DummyString(30000), wo));
ASSERT_OK(Put(0, Key(1), DummyString(40000), wo));
ASSERT_OK(Put(2, Key(1), DummyString(1), wo));
ASSERT_OK(Put(3, Key(2), DummyString(40000), wo));
// WriteBufferManager::buffer_size_ has exceeded after the previous write to
// db_ is completed.
std::unordered_set<WriteThread::Writer*> w_slowdown_set;
std::vector<port::Thread> threads;
int wait_count_db = 0;
int num_writers = 4;
InstrumentedMutex mutex;
InstrumentedCondVar cv(&mutex);
std::atomic<int> thread_num(0);
std::atomic<int> w_no_slowdown(0);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0",
"DBImpl::BackgroundCallFlush:start"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WBMStallInterface::BlockDB", [&](void*) {
{
InstrumentedMutexLock lock(&mutex);
wait_count_db++;
cv.SignalAll();
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WriteThread::WriteStall::Wait", [&](void* arg) {
{
InstrumentedMutexLock lock(&mutex);
WriteThread::Writer* w = reinterpret_cast<WriteThread::Writer*>(arg);
w_slowdown_set.insert(w);
// Allow the flush continue if all writer threads are blocked.
if (w_slowdown_set.size() + (unsigned long)w_no_slowdown.load(
std::memory_order_relaxed) ==
(unsigned long)num_writers) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
bool s1 = true, s2 = true;
std::function<void(int)> write_slow_down = [&](int cf) {
int a = thread_num.fetch_add(1);
std::string key = "foo" + std::to_string(a);
WriteOptions write_op;
write_op.no_slowdown = false;
Status tmp = Put(cf, Slice(key), DummyString(1), write_op);
InstrumentedMutexLock lock(&mutex);
s1 = s1 && tmp.ok();
};
std::function<void(int)> write_no_slow_down = [&](int cf) {
int a = thread_num.fetch_add(1);
std::string key = "foo" + std::to_string(a);
WriteOptions write_op;
write_op.no_slowdown = true;
Status tmp = Put(cf, Slice(key), DummyString(1), write_op);
{
InstrumentedMutexLock lock(&mutex);
s2 = s2 && !tmp.ok();
w_no_slowdown.fetch_add(1);
// Allow the flush continue if all writer threads are blocked.
if (w_slowdown_set.size() +
(unsigned long)w_no_slowdown.load(std::memory_order_relaxed) ==
(unsigned long)num_writers) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
};
// Flow:
// main_writer thread will write but will be blocked (as Flush will on hold,
// buffer_size_ has exceeded, thus will create stall in effect).
// |
// |
// multiple writer threads will be created to write across multiple columns
// with different values of WriteOptions.no_slowdown. Some of them will
// be blocked and some of them will return with Incomplete status.
// |
// |
// Last writer thread will write and when its blocked/return it will signal
// Flush to continue to clear the stall.
threads.emplace_back(write_slow_down, 1);
// Wait untill first thread (main_writer) writing to DB is blocked and then
// create the multiple writers which will be blocked from getting added to the
// queue because stall is in effect.
{
InstrumentedMutexLock lock(&mutex);
while (wait_count_db != 1) {
cv.Wait();
}
}
for (int i = 0; i < num_writers; i += 2) {
threads.emplace_back(write_no_slow_down, (i) % 4);
threads.emplace_back(write_slow_down, (i + 1) % 4);
}
for (auto& t : threads) {
t.join();
}
ASSERT_TRUE(s1);
ASSERT_TRUE(s2);
// Number of DBs blocked.
ASSERT_EQ(wait_count_db, 1);
// Number of Writer threads blocked.
ASSERT_EQ(w_slowdown_set.size(), num_writers / 2);
// Number of Writer threads with WriteOptions.no_slowdown = true.
ASSERT_EQ(w_no_slowdown.load(std::memory_order_relaxed), num_writers / 2);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Test multiple threads writing across multiple columns of db_ and different
// dbs by passing different values to WriteOption.no_slown_down.
TEST_P(DBWriteBufferManagerTest, MixedSlowDownOptionsMultipleDB) {
std::vector<std::string> dbnames;
std::vector<DB*> dbs;
int num_dbs = 4;
for (int i = 0; i < num_dbs; i++) {
dbs.push_back(nullptr);
dbnames.push_back(
test::PerThreadDBPath("db_shared_wb_db" + std::to_string(i)));
}
Options options = CurrentOptions();
options.arena_block_size = 4096;
options.write_buffer_size = 500000; // this is never hit
std::shared_ptr<Cache> cache = NewLRUCache(4 * 1024 * 1024, 2);
ASSERT_LT(cache->GetUsage(), 256 * 1024);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, cache, true));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(100000, nullptr, true));
}
CreateAndReopenWithCF({"cf1", "cf2"}, options);
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(DestroyDB(dbnames[i], options));
ASSERT_OK(DB::Open(options, dbnames[i], &(dbs[i])));
}
WriteOptions wo;
wo.disableWAL = true;
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Put(wo, Key(1), DummyString(20000)));
}
// Insert to db_.
ASSERT_OK(Put(0, Key(1), DummyString(30000), wo));
// WriteBufferManager::buffer_size_ has exceeded after the previous write to
// dbs[0] is completed.
std::vector<port::Thread> threads;
int wait_count_db = 0;
InstrumentedMutex mutex;
InstrumentedCondVar cv(&mutex);
std::unordered_set<WriteThread::Writer*> w_slowdown_set;
std::vector<port::Thread> writer_threads;
std::atomic<int> thread_num(0);
std::atomic<int> w_no_slowdown(0);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0",
"DBImpl::BackgroundCallFlush:start"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WBMStallInterface::BlockDB", [&](void*) {
InstrumentedMutexLock lock(&mutex);
wait_count_db++;
cv.Signal();
// Allow the flush continue if all writer threads are blocked.
if (w_slowdown_set.size() +
(unsigned long)(w_no_slowdown.load(std::memory_order_relaxed) +
wait_count_db) ==
(unsigned long)(2 * num_dbs + 1)) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"WriteThread::WriteStall::Wait", [&](void* arg) {
WriteThread::Writer* w = reinterpret_cast<WriteThread::Writer*>(arg);
InstrumentedMutexLock lock(&mutex);
w_slowdown_set.insert(w);
// Allow the flush continue if all writer threads are blocked.
if (w_slowdown_set.size() +
(unsigned long)(w_no_slowdown.load(std::memory_order_relaxed) +
wait_count_db) ==
(unsigned long)(2 * num_dbs + 1)) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
bool s1 = true, s2 = true;
std::function<void(DB*)> write_slow_down = [&](DB* db) {
int a = thread_num.fetch_add(1);
std::string key = "foo" + std::to_string(a);
WriteOptions write_op;
write_op.no_slowdown = false;
Status tmp = db->Put(write_op, Slice(key), DummyString(1));
InstrumentedMutexLock lock(&mutex);
s1 = s1 && tmp.ok();
};
std::function<void(DB*)> write_no_slow_down = [&](DB* db) {
int a = thread_num.fetch_add(1);
std::string key = "foo" + std::to_string(a);
WriteOptions write_op;
write_op.no_slowdown = true;
Status tmp = db->Put(write_op, Slice(key), DummyString(1));
{
InstrumentedMutexLock lock(&mutex);
s2 = s2 && !tmp.ok();
w_no_slowdown.fetch_add(1);
if (w_slowdown_set.size() +
(unsigned long)(w_no_slowdown.load(std::memory_order_relaxed) +
wait_count_db) ==
(unsigned long)(2 * num_dbs + 1)) {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::SharedWriteBufferAcrossCFs:0");
}
}
};
// Flow:
// first thread will write but will be blocked (as Flush will on hold,
// buffer_size_ has exceeded, thus will create stall in effect).
// |
// |
// multiple writer threads will be created to write across multiple columns
// of db_ and different DBs with different values of
// WriteOptions.no_slowdown. Some of them will be blocked and some of them
// will return with Incomplete status.
// |
// |
// Last writer thread will write and when its blocked/return it will signal
// Flush to continue to clear the stall.
threads.emplace_back(write_slow_down, db_);
// Wait untill first thread writing to DB is blocked and then
// create the multiple writers.
{
InstrumentedMutexLock lock(&mutex);
while (wait_count_db != 1) {
cv.Wait();
}
}
for (int i = 0; i < num_dbs; i += 2) {
// Write to multiple columns of db_.
writer_threads.emplace_back(write_slow_down, db_);
writer_threads.emplace_back(write_no_slow_down, db_);
// Write to different DBs.
threads.emplace_back(write_slow_down, dbs[i]);
threads.emplace_back(write_no_slow_down, dbs[i + 1]);
}
for (auto& t : threads) {
t.join();
}
for (auto& t : writer_threads) {
t.join();
}
ASSERT_TRUE(s1);
ASSERT_TRUE(s2);
// Number of DBs blocked.
ASSERT_EQ((num_dbs / 2) + 1, wait_count_db);
// Number of writer threads writing to db_ blocked from getting added to the
// queue.
ASSERT_EQ(w_slowdown_set.size(), num_dbs / 2);
// Number of threads with WriteOptions.no_slowdown = true.
ASSERT_EQ(w_no_slowdown.load(std::memory_order_relaxed), num_dbs);
// Clean up DBs.
for (int i = 0; i < num_dbs; i++) {
ASSERT_OK(dbs[i]->Close());
ASSERT_OK(DestroyDB(dbnames[i], options));
delete dbs[i];
}
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Tests a `WriteBufferManager` constructed with `allow_stall == false` does not
// thrash memtable switching when full and a CF receives multiple writes.
// Instead, we expect to switch a CF's memtable for flush only when that CF does
// not have any pending or running flush.
//
// This test uses multiple DBs each with a single CF instead of a single DB
// with multiple CFs. That way we can control which CF is considered for switch
// by writing to that CF's DB.
//
// Not supported in LITE mode due to `GetProperty()` unavailable.
TEST_P(DBWriteBufferManagerTest, StopSwitchingMemTablesOnceFlushing) {
Options options = CurrentOptions();
options.arena_block_size = 4 << 10; // 4KB
options.write_buffer_size = 1 << 20; // 1MB
std::shared_ptr<Cache> cache =
NewLRUCache(4 << 20 /* capacity (4MB) */, 2 /* num_shard_bits */);
ASSERT_LT(cache->GetUsage(), 256 << 10 /* 256KB */);
cost_cache_ = GetParam();
if (cost_cache_) {
options.write_buffer_manager.reset(new WriteBufferManager(
512 << 10 /* buffer_size (512KB) */, cache, false /* allow_stall */));
} else {
options.write_buffer_manager.reset(
new WriteBufferManager(512 << 10 /* buffer_size (512KB) */,
nullptr /* cache */, false /* allow_stall */));
}
Reopen(options);
std::string dbname = test::PerThreadDBPath("db_shared_wbm_db");
DB* shared_wbm_db = nullptr;
ASSERT_OK(DestroyDB(dbname, options));
ASSERT_OK(DB::Open(options, dbname, &shared_wbm_db));
// The last write will make WBM need flush, but it won't flush yet.
ASSERT_OK(Put(Key(1), DummyString(256 << 10 /* 256KB */), WriteOptions()));
ASSERT_FALSE(options.write_buffer_manager->ShouldFlush());
ASSERT_OK(Put(Key(1), DummyString(256 << 10 /* 256KB */), WriteOptions()));
ASSERT_TRUE(options.write_buffer_manager->ShouldFlush());
// Flushes will be pending, not running because flush threads are blocked.
test::SleepingBackgroundTask sleeping_task_high;
env_->Schedule(&test::SleepingBackgroundTask::DoSleepTask,
&sleeping_task_high, Env::Priority::HIGH);
for (int i = 0; i < 3; ++i) {
ASSERT_OK(
shared_wbm_db->Put(WriteOptions(), Key(1), DummyString(1 /* len */)));
std::string prop;
ASSERT_TRUE(
shared_wbm_db->GetProperty("rocksdb.num-immutable-mem-table", &prop));
ASSERT_EQ(std::to_string(i > 0 ? 1 : 0), prop);
ASSERT_TRUE(
shared_wbm_db->GetProperty("rocksdb.mem-table-flush-pending", &prop));
ASSERT_EQ(std::to_string(i > 0 ? 1 : 0), prop);
}
// Clean up DBs.
sleeping_task_high.WakeUp();
sleeping_task_high.WaitUntilDone();
ASSERT_OK(shared_wbm_db->Close());
ASSERT_OK(DestroyDB(dbname, options));
delete shared_wbm_db;
}
TEST_F(DBWriteBufferManagerTest, RuntimeChangeableAllowStall) {
constexpr int kBigValue = 10000;
Options options = CurrentOptions();
options.write_buffer_manager.reset(
new WriteBufferManager(1, nullptr /* cache */, true /* allow_stall */));
DestroyAndReopen(options);
// Pause flush thread so that
// (a) the only way to exist write stall below is to change the `allow_stall`
// (b) the write stall is "stable" without being interfered by flushes so that
// we can check it without flakiness
std::unique_ptr<test::SleepingBackgroundTask> sleeping_task(
new test::SleepingBackgroundTask());
env_->SetBackgroundThreads(1, Env::HIGH);
env_->Schedule(&test::SleepingBackgroundTask::DoSleepTask,
sleeping_task.get(), Env::Priority::HIGH);
sleeping_task->WaitUntilSleeping();
// Test 1: test setting `allow_stall` from true to false
//
// Assert existence of a write stall
WriteOptions wo_no_slowdown;
wo_no_slowdown.no_slowdown = true;
Status s = Put(Key(0), DummyString(kBigValue), wo_no_slowdown);
ASSERT_TRUE(s.IsIncomplete());
ASSERT_TRUE(s.ToString().find("Write stall") != std::string::npos);
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency(
{{"WBMStallInterface::BlockDB",
"DBWriteBufferManagerTest::RuntimeChangeableThreadSafeParameters::"
"ChangeParameter"}});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
// Test `SetAllowStall()`
port::Thread thread1([&] { ASSERT_OK(Put(Key(0), DummyString(kBigValue))); });
port::Thread thread2([&] {
TEST_SYNC_POINT(
"DBWriteBufferManagerTest::RuntimeChangeableThreadSafeParameters::"
"ChangeParameter");
options.write_buffer_manager->SetAllowStall(false);
});
// Verify `allow_stall` is successfully set to false in thread2.
// Othwerwise, thread1's write will be stalled and this test will hang
// forever.
thread1.join();
thread2.join();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
// Test 2: test setting `allow_stall` from false to true
//
// Assert no write stall
ASSERT_OK(Put(Key(0), DummyString(kBigValue), wo_no_slowdown));
// Test `SetAllowStall()`
options.write_buffer_manager->SetAllowStall(true);
// Verify `allow_stall` is successfully set to true.
// Otherwise the following write will not be stalled and therefore succeed.
s = Put(Key(0), DummyString(kBigValue), wo_no_slowdown);
ASSERT_TRUE(s.IsIncomplete());
ASSERT_TRUE(s.ToString().find("Write stall") != std::string::npos);
sleeping_task->WakeUp();
}
INSTANTIATE_TEST_CASE_P(DBWriteBufferManagerTest, DBWriteBufferManagerTest,
testing::Bool());
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
RegisterCustomObjects(argc, argv);
return RUN_ALL_TESTS();
}