rocksdb/db/compaction_job_test.cc
Andres Noetzli 014fd55adc Support for SingleDelete()
Summary:
This patch fixes #7460559. It introduces SingleDelete as a new database
operation. This operation can be used to delete keys that were never
overwritten (no put following another put of the same key). If an overwritten
key is single deleted the behavior is undefined. Single deletion of a
non-existent key has no effect but multiple consecutive single deletions are
not allowed (see limitations).

In contrast to the conventional Delete() operation, the deletion entry is
removed along with the value when the two are lined up in a compaction. Note:
The semantics are similar to @igor's prototype that allowed to have this
behavior on the granularity of a column family (
https://reviews.facebook.net/D42093 ). This new patch, however, is more
aggressive when it comes to removing tombstones: It removes the SingleDelete
together with the value whenever there is no snapshot between them while the
older patch only did this when the sequence number of the deletion was older
than the earliest snapshot.

Most of the complex additions are in the Compaction Iterator, all other changes
should be relatively straightforward. The patch also includes basic support for
single deletions in db_stress and db_bench.

Limitations:
- Not compatible with cuckoo hash tables
- Single deletions cannot be used in combination with merges and normal
  deletions on the same key (other keys are not affected by this)
- Consecutive single deletions are currently not allowed (and older version of
  this patch supported this so it could be resurrected if needed)

Test Plan: make all check

Reviewers: yhchiang, sdong, rven, anthony, yoshinorim, igor

Reviewed By: igor

Subscribers: maykov, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D43179
2015-09-17 11:42:56 -07:00

590 lines
20 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 <tuple>
#include "db/compaction_job.h"
#include "db/column_family.h"
#include "db/version_set.h"
#include "db/writebuffer.h"
#include "rocksdb/cache.h"
#include "rocksdb/db.h"
#include "rocksdb/options.h"
#include "table/mock_table.h"
#include "util/file_reader_writer.h"
#include "util/string_util.h"
#include "util/testharness.h"
#include "util/testutil.h"
#include "utilities/merge_operators.h"
namespace rocksdb {
namespace {
void VerifyInitializationOfCompactionJobStats(
const CompactionJobStats& compaction_job_stats) {
#if !defined(IOS_CROSS_COMPILE)
ASSERT_EQ(compaction_job_stats.elapsed_micros, 0U);
ASSERT_EQ(compaction_job_stats.num_input_records, 0U);
ASSERT_EQ(compaction_job_stats.num_input_files, 0U);
ASSERT_EQ(compaction_job_stats.num_input_files_at_output_level, 0U);
ASSERT_EQ(compaction_job_stats.num_output_records, 0U);
ASSERT_EQ(compaction_job_stats.num_output_files, 0U);
ASSERT_EQ(compaction_job_stats.is_manual_compaction, true);
ASSERT_EQ(compaction_job_stats.total_input_bytes, 0U);
ASSERT_EQ(compaction_job_stats.total_output_bytes, 0U);
ASSERT_EQ(compaction_job_stats.total_input_raw_key_bytes, 0U);
ASSERT_EQ(compaction_job_stats.total_input_raw_value_bytes, 0U);
ASSERT_EQ(compaction_job_stats.smallest_output_key_prefix[0], 0);
ASSERT_EQ(compaction_job_stats.largest_output_key_prefix[0], 0);
ASSERT_EQ(compaction_job_stats.num_records_replaced, 0U);
ASSERT_EQ(compaction_job_stats.num_input_deletion_records, 0U);
ASSERT_EQ(compaction_job_stats.num_expired_deletion_records, 0U);
ASSERT_EQ(compaction_job_stats.num_corrupt_keys, 0U);
#endif // !defined(IOS_CROSS_COMPILE)
}
} // namespace
// TODO(icanadi) Make it simpler once we mock out VersionSet
class CompactionJobTest : public testing::Test {
public:
CompactionJobTest()
: env_(Env::Default()),
dbname_(test::TmpDir() + "/compaction_job_test"),
mutable_cf_options_(Options(), ImmutableCFOptions(Options())),
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());
}
std::string GenerateFileName(uint64_t file_number) {
FileMetaData meta;
std::vector<DbPath> db_paths;
db_paths.emplace_back(dbname_, std::numeric_limits<uint64_t>::max());
meta.fd = FileDescriptor(file_number, 0, 0);
return TableFileName(db_paths, meta.fd.GetNumber(), meta.fd.GetPathId());
}
std::string KeyStr(const std::string& user_key, const SequenceNumber seq_num,
const ValueType t) {
return InternalKey(user_key, seq_num, t).Encode().ToString();
}
void AddMockFile(const stl_wrappers::KVMap& contents, int level = 0) {
assert(contents.size() > 0);
bool first_key = true;
std::string smallest, largest;
InternalKey smallest_key, largest_key;
SequenceNumber smallest_seqno = kMaxSequenceNumber;
SequenceNumber largest_seqno = 0;
for (auto kv : contents) {
ParsedInternalKey key;
std::string skey;
std::string value;
std::tie(skey, value) = kv;
ParseInternalKey(skey, &key);
smallest_seqno = std::min(smallest_seqno, key.sequence);
largest_seqno = std::max(largest_seqno, key.sequence);
if (first_key ||
cfd_->user_comparator()->Compare(key.user_key, smallest) < 0) {
smallest.assign(key.user_key.data(), key.user_key.size());
smallest_key.DecodeFrom(skey);
}
if (first_key ||
cfd_->user_comparator()->Compare(key.user_key, largest) > 0) {
largest.assign(key.user_key.data(), key.user_key.size());
largest_key.DecodeFrom(skey);
}
first_key = false;
}
uint64_t file_number = versions_->NewFileNumber();
EXPECT_OK(mock_table_factory_->CreateMockTable(
env_, GenerateFileName(file_number), std::move(contents)));
VersionEdit edit;
edit.AddFile(level, file_number, 0, 10, smallest_key, largest_key,
smallest_seqno, largest_seqno, false);
mutex_.Lock();
versions_->LogAndApply(versions_->GetColumnFamilySet()->GetDefault(),
mutable_cf_options_, &edit, &mutex_);
mutex_.Unlock();
}
void SetLastSequence(const SequenceNumber sequence_number) {
versions_->SetLastSequence(sequence_number + 1);
}
// returns expected result after compaction
stl_wrappers::KVMap CreateTwoFiles(bool gen_corrupted_keys) {
auto expected_results = mock::MakeMockFile();
const int kKeysPerFile = 10000;
const int kCorruptKeysPerFile = 200;
const int kMatchingKeys = kKeysPerFile / 2;
SequenceNumber sequence_number = 0;
auto corrupt_id = [&](int id) {
return gen_corrupted_keys && id > 0 && id <= kCorruptKeysPerFile;
};
for (int i = 0; i < 2; ++i) {
auto contents = mock::MakeMockFile();
for (int k = 0; k < kKeysPerFile; ++k) {
auto key = ToString(i * kMatchingKeys + k);
auto value = ToString(i * kKeysPerFile + k);
InternalKey internal_key(key, ++sequence_number, kTypeValue);
// This is how the key will look like once it's written in bottommost
// file
InternalKey bottommost_internal_key(key, 0, kTypeValue);
if (corrupt_id(k)) {
test::CorruptKeyType(&internal_key);
test::CorruptKeyType(&bottommost_internal_key);
}
contents.insert({ internal_key.Encode().ToString(), value });
if (i == 1 || k < kMatchingKeys || corrupt_id(k - kMatchingKeys)) {
expected_results.insert(
{ bottommost_internal_key.Encode().ToString(), value });
}
}
AddMockFile(contents);
}
SetLastSequence(sequence_number);
return expected_results;
}
void NewDB(std::shared_ptr<MergeOperator> merge_operator = nullptr) {
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), env_options_));
{
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);
std::vector<ColumnFamilyDescriptor> column_families;
cf_options_.table_factory = mock_table_factory_;
cf_options_.merge_operator = merge_operator;
column_families.emplace_back(kDefaultColumnFamilyName, cf_options_);
EXPECT_OK(versions_->Recover(column_families, false));
cfd_ = versions_->GetColumnFamilySet()->GetDefault();
}
void RunCompaction(const std::vector<std::vector<FileMetaData*>>& input_files,
const stl_wrappers::KVMap& expected_results,
const std::vector<SequenceNumber>& snapshots = {}) {
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
size_t num_input_files = 0;
std::vector<CompactionInputFiles> compaction_input_files;
for (size_t level = 0; level < input_files.size(); level++) {
auto level_files = input_files[level];
CompactionInputFiles compaction_level;
compaction_level.level = static_cast<int>(level);
compaction_level.files.insert(compaction_level.files.end(),
level_files.begin(), level_files.end());
compaction_input_files.push_back(compaction_level);
num_input_files += level_files.size();
}
Compaction compaction(cfd->current()->storage_info(),
*cfd->GetLatestMutableCFOptions(),
compaction_input_files, 1, 1024 * 1024, 10, 0,
kNoCompression, {}, true);
compaction.SetInputVersion(cfd->current());
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, db_options_.info_log.get());
mutex_.Lock();
EventLogger event_logger(db_options_.info_log.get());
CompactionJob compaction_job(0, &compaction, db_options_, env_options_,
versions_.get(), &shutting_down_, &log_buffer,
nullptr, nullptr, nullptr, snapshots,
table_cache_, &event_logger, false, false,
dbname_, &compaction_job_stats_);
VerifyInitializationOfCompactionJobStats(compaction_job_stats_);
compaction_job.Prepare();
mutex_.Unlock();
Status s;
s = compaction_job.Run();
ASSERT_OK(s);
mutex_.Lock();
ASSERT_OK(compaction_job.Install(*cfd->GetLatestMutableCFOptions(),
&mutex_));
mutex_.Unlock();
ASSERT_GE(compaction_job_stats_.elapsed_micros, 0U);
ASSERT_EQ(compaction_job_stats_.num_input_files, num_input_files);
ASSERT_EQ(compaction_job_stats_.num_output_files, 1U);
mock_table_factory_->AssertLatestFile(expected_results);
}
Env* env_;
std::string dbname_;
EnvOptions env_options_;
MutableCFOptions mutable_cf_options_;
std::shared_ptr<Cache> table_cache_;
WriteController write_controller_;
DBOptions db_options_;
ColumnFamilyOptions cf_options_;
WriteBuffer write_buffer_;
std::unique_ptr<VersionSet> versions_;
InstrumentedMutex mutex_;
std::atomic<bool> shutting_down_;
std::shared_ptr<mock::MockTableFactory> mock_table_factory_;
CompactionJobStats compaction_job_stats_;
ColumnFamilyData* cfd_;
};
TEST_F(CompactionJobTest, Simple) {
NewDB();
auto expected_results = CreateTwoFiles(false);
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
auto files = cfd->current()->storage_info()->LevelFiles(0);
ASSERT_EQ(2U, files.size());
RunCompaction({ files }, expected_results);
}
TEST_F(CompactionJobTest, SimpleCorrupted) {
NewDB();
auto expected_results = CreateTwoFiles(true);
auto cfd = versions_->GetColumnFamilySet()->GetDefault();
auto files = cfd->current()->storage_info()->LevelFiles(0);
RunCompaction({ files }, expected_results);
ASSERT_EQ(compaction_job_stats_.num_corrupt_keys, 400U);
}
TEST_F(CompactionJobTest, SimpleDeletion) {
NewDB();
auto file1 = mock::MakeMockFile({{KeyStr("c", 4U, kTypeDeletion), ""},
{KeyStr("c", 3U, kTypeValue), "val"}});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({{KeyStr("b", 2U, kTypeValue), "val"},
{KeyStr("b", 1U, kTypeValue), "val"}});
AddMockFile(file2);
auto expected_results =
mock::MakeMockFile({{KeyStr("b", 0U, kTypeValue), "val"}});
SetLastSequence(4U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({ files }, expected_results);
}
TEST_F(CompactionJobTest, SimpleOverwrite) {
NewDB();
auto file1 = mock::MakeMockFile({
{KeyStr("a", 3U, kTypeValue), "val2"},
{KeyStr("b", 4U, kTypeValue), "val3"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({{KeyStr("a", 1U, kTypeValue), "val"},
{KeyStr("b", 2U, kTypeValue), "val"}});
AddMockFile(file2);
auto expected_results =
mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "val2"},
{KeyStr("b", 0U, kTypeValue), "val3"}});
SetLastSequence(4U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({ files }, expected_results);
}
TEST_F(CompactionJobTest, SimpleNonLastLevel) {
NewDB();
auto file1 = mock::MakeMockFile({
{KeyStr("a", 5U, kTypeValue), "val2"},
{KeyStr("b", 6U, kTypeValue), "val3"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({{KeyStr("a", 3U, kTypeValue), "val"},
{KeyStr("b", 4U, kTypeValue), "val"}});
AddMockFile(file2, 1);
auto file3 = mock::MakeMockFile({{KeyStr("a", 1U, kTypeValue), "val"},
{KeyStr("b", 2U, kTypeValue), "val"}});
AddMockFile(file3, 2);
// Because level 1 is not the last level, the sequence numbers of a and b
// cannot be set to 0
auto expected_results =
mock::MakeMockFile({{KeyStr("a", 5U, kTypeValue), "val2"},
{KeyStr("b", 6U, kTypeValue), "val3"}});
SetLastSequence(6U);
auto lvl0_files = cfd_->current()->storage_info()->LevelFiles(0);
auto lvl1_files = cfd_->current()->storage_info()->LevelFiles(1);
RunCompaction({ lvl0_files, lvl1_files }, expected_results);
}
TEST_F(CompactionJobTest, SimpleMerge) {
auto merge_op = MergeOperators::CreateStringAppendOperator();
NewDB(merge_op);
auto file1 = mock::MakeMockFile({
{KeyStr("a", 5U, kTypeMerge), "5"},
{KeyStr("a", 4U, kTypeMerge), "4"},
{KeyStr("a", 3U, kTypeValue), "3"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile(
{{KeyStr("b", 2U, kTypeMerge), "2"}, {KeyStr("b", 1U, kTypeValue), "1"}});
AddMockFile(file2);
auto expected_results =
mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "3,4,5"},
{KeyStr("b", 0U, kTypeValue), "1,2"}});
SetLastSequence(5U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({ files }, expected_results);
}
TEST_F(CompactionJobTest, NonAssocMerge) {
auto merge_op = MergeOperators::CreateStringAppendTESTOperator();
NewDB(merge_op);
auto file1 = mock::MakeMockFile({
{KeyStr("a", 5U, kTypeMerge), "5"},
{KeyStr("a", 4U, kTypeMerge), "4"},
{KeyStr("a", 3U, kTypeMerge), "3"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile(
{{KeyStr("b", 2U, kTypeMerge), "2"}, {KeyStr("b", 1U, kTypeMerge), "1"}});
AddMockFile(file2);
auto expected_results =
mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "3,4,5"},
{KeyStr("b", 2U, kTypeMerge), "2"},
{KeyStr("b", 1U, kTypeMerge), "1"}});
SetLastSequence(5U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({ files }, expected_results);
}
TEST_F(CompactionJobTest, SimpleSingleDelete) {
NewDB();
auto file1 = mock::MakeMockFile({
{KeyStr("a", 5U, kTypeDeletion), ""},
{KeyStr("b", 6U, kTypeSingleDeletion), ""},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({{KeyStr("a", 3U, kTypeValue), "val"},
{KeyStr("b", 4U, kTypeValue), "val"}});
AddMockFile(file2);
auto file3 = mock::MakeMockFile({
{KeyStr("a", 1U, kTypeValue), "val"},
});
AddMockFile(file3, 2);
auto expected_results =
mock::MakeMockFile({{KeyStr("a", 5U, kTypeDeletion), ""}});
SetLastSequence(6U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({files}, expected_results);
}
TEST_F(CompactionJobTest, SingleDeleteSnapshots) {
NewDB();
auto file1 = mock::MakeMockFile({{KeyStr("A", 12U, kTypeSingleDeletion), ""},
{KeyStr("a", 12U, kTypeSingleDeletion), ""},
{KeyStr("b", 21U, kTypeSingleDeletion), ""},
{KeyStr("c", 22U, kTypeSingleDeletion), ""},
{KeyStr("d", 9U, kTypeSingleDeletion), ""}});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({{KeyStr("0", 2U, kTypeSingleDeletion), ""},
{KeyStr("a", 11U, kTypeValue), "val1"},
{KeyStr("b", 11U, kTypeValue), "val2"},
{KeyStr("c", 21U, kTypeValue), "val3"},
{KeyStr("d", 8U, kTypeValue), "val4"},
{KeyStr("e", 2U, kTypeSingleDeletion), ""}});
AddMockFile(file2);
auto file3 = mock::MakeMockFile({{KeyStr("A", 1U, kTypeValue), "val"},
{KeyStr("e", 1U, kTypeValue), "val"}});
AddMockFile(file3, 2);
auto expected_results =
mock::MakeMockFile({{KeyStr("A", 12U, kTypeSingleDeletion), ""},
{KeyStr("b", 21U, kTypeSingleDeletion), ""},
{KeyStr("b", 11U, kTypeValue), "val2"},
{KeyStr("e", 2U, kTypeSingleDeletion), ""}});
SetLastSequence(22U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({files}, expected_results, {10U, 20U});
}
TEST_F(CompactionJobTest, SingleDeleteZeroSeq) {
NewDB();
auto file1 = mock::MakeMockFile({
{KeyStr("A", 10U, kTypeSingleDeletion), ""},
{KeyStr("dummy", 5U, kTypeValue), "val2"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({
{KeyStr("A", 0U, kTypeValue), "val"},
});
AddMockFile(file2);
auto expected_results = mock::MakeMockFile({
{KeyStr("dummy", 0U, kTypeValue), "val2"},
});
SetLastSequence(22U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({files}, expected_results, {});
}
TEST_F(CompactionJobTest, MultiSingleDelete) {
// Tests three scenarios involving multiple single delete/put pairs:
//
// A: Put Snapshot SDel Put SDel -> Put Snapshot SDel
// B: Put SDel Put SDel -> (Removed)
// C: SDel Put SDel Snapshot Put -> Snapshot Put
// D: (Put) SDel Snapshot Put SDel -> (Put) SDel Snapshot
NewDB();
auto file1 = mock::MakeMockFile({
{KeyStr("A", 14U, kTypeSingleDeletion), ""},
{KeyStr("A", 13U, kTypeValue), "val5"},
{KeyStr("A", 12U, kTypeSingleDeletion), ""},
{KeyStr("B", 14U, kTypeSingleDeletion), ""},
{KeyStr("B", 13U, kTypeValue), "val2"},
{KeyStr("C", 14U, kTypeValue), "val3"},
{KeyStr("D", 12U, kTypeSingleDeletion), ""},
{KeyStr("D", 11U, kTypeValue), "val4"},
});
AddMockFile(file1);
auto file2 = mock::MakeMockFile({
{KeyStr("A", 10U, kTypeValue), "val"},
{KeyStr("B", 12U, kTypeSingleDeletion), ""},
{KeyStr("B", 11U, kTypeValue), "val2"},
{KeyStr("C", 10U, kTypeSingleDeletion), ""},
{KeyStr("C", 9U, kTypeValue), "val6"},
{KeyStr("C", 8U, kTypeSingleDeletion), ""},
{KeyStr("D", 10U, kTypeSingleDeletion), ""},
});
AddMockFile(file2);
auto file3 = mock::MakeMockFile({
{KeyStr("D", 11U, kTypeValue), "val"},
});
AddMockFile(file3, 2);
auto expected_results = mock::MakeMockFile({
{KeyStr("A", 12U, kTypeSingleDeletion), ""},
{KeyStr("A", 10U, kTypeValue), "val"},
{KeyStr("C", 14U, kTypeValue), "val3"},
{KeyStr("D", 10U, kTypeSingleDeletion), ""},
});
SetLastSequence(22U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({files}, expected_results, {10U});
}
// This test documents the behavior where a corrupt key follows a deletion or a
// single deletion and the (single) deletion gets removed while the corrupt key
// gets written out. TODO(noetzli): We probably want a better way to treat
// corrupt keys.
TEST_F(CompactionJobTest, CorruptionAfterDeletion) {
NewDB();
auto file1 =
mock::MakeMockFile({{test::KeyStr("A", 6U, kTypeValue), "val3"},
{test::KeyStr("a", 5U, kTypeDeletion), ""},
{test::KeyStr("a", 4U, kTypeValue, true), "val"}});
AddMockFile(file1);
auto file2 =
mock::MakeMockFile({{test::KeyStr("b", 3U, kTypeSingleDeletion), ""},
{test::KeyStr("b", 2U, kTypeValue, true), "val"},
{test::KeyStr("c", 1U, kTypeValue), "val2"}});
AddMockFile(file2);
auto expected_results =
mock::MakeMockFile({{test::KeyStr("A", 0U, kTypeValue), "val3"},
{test::KeyStr("a", 0U, kTypeValue, true), "val"},
{test::KeyStr("b", 0U, kTypeValue, true), "val"},
{test::KeyStr("c", 0U, kTypeValue), "val2"}});
SetLastSequence(6U);
auto files = cfd_->current()->storage_info()->LevelFiles(0);
RunCompaction({files}, expected_results);
}
} // namespace rocksdb
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}