rocksdb/db/flush_job_test.cc
Igor Canadi 4ab26c5ad1 Smarter purging during flush
Summary:
Currently, we only purge duplicate keys and deletions during flush if `earliest_seqno_in_memtable <= newest_snapshot`. This means that the newest snapshot happened before we first created the memtable. This is almost never true for MyRocks and MongoRocks.

This patch makes purging during flush able to understand snapshots. The main logic is copied from compaction_job.cc, although the logic over there is much more complicated and extensive. However, we should try to merge the common functionality at some point.

I need this patch to implement no_overwrite_i_promise functionality for flush. We'll also need this to support SingleDelete() during Flush(). @yoshinorim requested the feature.

Test Plan:
make check
I had to adjust some unit tests to understand this new behavior

Reviewers: yhchiang, yoshinorim, anthony, sdong, noetzli

Reviewed By: noetzli

Subscribers: yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42087
2015-08-24 11:11:12 -07:00

213 lines
7.5 KiB
C++

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
#include <algorithm>
#include <map>
#include <string>
#include "db/flush_job.h"
#include "db/column_family.h"
#include "db/version_set.h"
#include "db/writebuffer.h"
#include "rocksdb/cache.h"
#include "util/file_reader_writer.h"
#include "util/string_util.h"
#include "util/testharness.h"
#include "util/testutil.h"
#include "table/mock_table.h"
namespace rocksdb {
// TODO(icanadi) Mock out everything else:
// 1. VersionSet
// 2. Memtable
class FlushJobTest : public testing::Test {
public:
FlushJobTest()
: env_(Env::Default()),
dbname_(test::TmpDir() + "/flush_job_test"),
table_cache_(NewLRUCache(50000, 16)),
write_buffer_(db_options_.db_write_buffer_size),
versions_(new VersionSet(dbname_, &db_options_, env_options_,
table_cache_.get(), &write_buffer_,
&write_controller_)),
shutting_down_(false),
mock_table_factory_(new mock::MockTableFactory()) {
EXPECT_OK(env_->CreateDirIfMissing(dbname_));
db_options_.db_paths.emplace_back(dbname_,
std::numeric_limits<uint64_t>::max());
// TODO(icanadi) Remove this once we mock out VersionSet
NewDB();
std::vector<ColumnFamilyDescriptor> column_families;
cf_options_.table_factory = mock_table_factory_;
column_families.emplace_back(kDefaultColumnFamilyName, cf_options_);
EXPECT_OK(versions_->Recover(column_families, false));
}
void NewDB() {
VersionEdit new_db;
new_db.SetLogNumber(0);
new_db.SetNextFile(2);
new_db.SetLastSequence(0);
const std::string manifest = DescriptorFileName(dbname_, 1);
unique_ptr<WritableFile> file;
Status s = env_->NewWritableFile(
manifest, &file, env_->OptimizeForManifestWrite(env_options_));
ASSERT_OK(s);
unique_ptr<WritableFileWriter> file_writer(
new WritableFileWriter(std::move(file), EnvOptions()));
{
log::Writer log(std::move(file_writer));
std::string record;
new_db.EncodeTo(&record);
s = log.AddRecord(record);
}
ASSERT_OK(s);
// Make "CURRENT" file that points to the new manifest file.
s = SetCurrentFile(env_, dbname_, 1, nullptr);
}
Env* env_;
std::string dbname_;
EnvOptions env_options_;
std::shared_ptr<Cache> table_cache_;
WriteController write_controller_;
DBOptions db_options_;
WriteBuffer write_buffer_;
ColumnFamilyOptions cf_options_;
std::unique_ptr<VersionSet> versions_;
InstrumentedMutex mutex_;
std::atomic<bool> shutting_down_;
std::shared_ptr<mock::MockTableFactory> mock_table_factory_;
};
TEST_F(FlushJobTest, Empty) {
JobContext job_context(0);
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
EventLogger event_logger(db_options_.info_log.get());
FlushJob flush_job(dbname_, versions_->GetColumnFamilySet()->GetDefault(),
db_options_, *cfd->GetLatestMutableCFOptions(),
env_options_, versions_.get(), &mutex_, &shutting_down_,
{}, &job_context, nullptr, nullptr, nullptr,
kNoCompression, nullptr, &event_logger);
ASSERT_OK(flush_job.Run());
job_context.Clean();
}
TEST_F(FlushJobTest, NonEmpty) {
JobContext job_context(0);
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
auto new_mem = cfd->ConstructNewMemtable(*cfd->GetLatestMutableCFOptions(),
kMaxSequenceNumber);
new_mem->Ref();
mock::MockFileContents inserted_keys;
// Test data:
// seqno [ 1, 2 ... 8998, 8999, 9000, 9001, 9002 ... 9999 ]
// key [ 1001, 1002 ... 9998, 9999, 0, 1, 2 ... 999 ]
// Expected:
// smallest_key = "0"
// largest_key = "9999"
// smallest_seqno = 1
// smallest_seqno = 9999
for (int i = 1; i < 10000; ++i) {
std::string key(ToString((i + 1000) % 10000));
std::string value("value" + key);
new_mem->Add(SequenceNumber(i), kTypeValue, key, value);
InternalKey internal_key(key, SequenceNumber(i), kTypeValue);
inserted_keys.insert({internal_key.Encode().ToString(), value});
}
autovector<MemTable*> to_delete;
cfd->imm()->Add(new_mem, &to_delete);
for (auto& m : to_delete) {
delete m;
}
EventLogger event_logger(db_options_.info_log.get());
FlushJob flush_job(dbname_, versions_->GetColumnFamilySet()->GetDefault(),
db_options_, *cfd->GetLatestMutableCFOptions(),
env_options_, versions_.get(), &mutex_, &shutting_down_,
{}, &job_context, nullptr, nullptr, nullptr,
kNoCompression, nullptr, &event_logger);
FileMetaData fd;
mutex_.Lock();
ASSERT_OK(flush_job.Run(&fd));
mutex_.Unlock();
ASSERT_EQ(ToString(0), fd.smallest.user_key().ToString());
ASSERT_EQ(ToString(9999), fd.largest.user_key().ToString());
ASSERT_EQ(1, fd.smallest_seqno);
ASSERT_EQ(9999, fd.largest_seqno);
mock_table_factory_->AssertSingleFile(inserted_keys);
job_context.Clean();
}
TEST_F(FlushJobTest, Snapshots) {
JobContext job_context(0);
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
auto new_mem = cfd->ConstructNewMemtable(*cfd->GetLatestMutableCFOptions(),
kMaxSequenceNumber);
std::vector<SequenceNumber> snapshots;
std::set<SequenceNumber> snapshots_set;
int keys = 10000;
int max_inserts_per_keys = 8;
Random rnd(301);
for (int i = 0; i < keys / 2; ++i) {
snapshots.push_back(rnd.Uniform(keys * (max_inserts_per_keys / 2)) + 1);
snapshots_set.insert(snapshots.back());
}
std::sort(snapshots.begin(), snapshots.end());
new_mem->Ref();
SequenceNumber current_seqno = 0;
mock::MockFileContents inserted_keys;
for (int i = 1; i < keys; ++i) {
std::string key(ToString(i));
int insertions = rnd.Uniform(max_inserts_per_keys);
for (int j = 0; j < insertions; ++j) {
std::string value(test::RandomHumanReadableString(&rnd, 10));
auto seqno = ++current_seqno;
new_mem->Add(SequenceNumber(seqno), kTypeValue, key, value);
// a key is visible only if:
// 1. it's the last one written (j == insertions - 1)
// 2. there's a snapshot pointing at it
bool visible = (j == insertions - 1) ||
(snapshots_set.find(seqno) != snapshots_set.end());
if (visible) {
InternalKey internal_key(key, seqno, kTypeValue);
inserted_keys.insert({internal_key.Encode().ToString(), value});
}
}
}
autovector<MemTable*> to_delete;
cfd->imm()->Add(new_mem, &to_delete);
for (auto& m : to_delete) {
delete m;
}
EventLogger event_logger(db_options_.info_log.get());
FlushJob flush_job(dbname_, versions_->GetColumnFamilySet()->GetDefault(),
db_options_, *cfd->GetLatestMutableCFOptions(),
env_options_, versions_.get(), &mutex_, &shutting_down_,
snapshots, &job_context, nullptr, nullptr, nullptr,
kNoCompression, nullptr, &event_logger);
mutex_.Lock();
ASSERT_OK(flush_job.Run());
mutex_.Unlock();
mock_table_factory_->AssertSingleFile(inserted_keys);
job_context.Clean();
}
} // namespace rocksdb
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}