rocksdb/util/testutil.cc
Sagar Vemuri 04c11b867d Level Compaction with TTL
Summary:
Level Compaction with TTL.

As of today, a file could exist in the LSM tree without going through the compaction process for a really long time if there are no updates to the data in the file's key range. For example, in certain use cases, the keys are not actually "deleted"; instead they are just set to empty values. There might not be any more writes to this "deleted" key range, and if so, such data could remain in the LSM for a really long time resulting in wasted space.

Introducing a TTL could solve this problem. Files (and, in turn, data) older than TTL will be scheduled for compaction when there is no other background work. This will make the data go through the regular compaction process and get rid of old unwanted data.
This also has the (good) side-effect of all the data in the non-bottommost level being newer than ttl, and all data in the bottommost level older than ttl. It could lead to more writes while reducing space.

This functionality can be controlled by the newly introduced column family option -- ttl.

TODO for later:
- Make ttl mutable
- Extend TTL to Universal compaction as well? (TTL is already supported in FIFO)
- Maybe deprecate CompactionOptionsFIFO.ttl in favor of this new ttl option.
Closes https://github.com/facebook/rocksdb/pull/3591

Differential Revision: D7275442

Pulled By: sagar0

fbshipit-source-id: dcba484717341200d419b0953dafcdf9eb2f0267
2018-04-02 22:14:28 -07:00

407 lines
13 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 "util/testutil.h"
#include <cctype>
#include <sstream>
#include "db/memtable_list.h"
#include "port/port.h"
#include "util/file_reader_writer.h"
namespace rocksdb {
namespace test {
Slice RandomString(Random* rnd, int len, std::string* dst) {
dst->resize(len);
for (int i = 0; i < len; i++) {
(*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~'
}
return Slice(*dst);
}
extern std::string RandomHumanReadableString(Random* rnd, int len) {
std::string ret;
ret.resize(len);
for (int i = 0; i < len; ++i) {
ret[i] = static_cast<char>('a' + rnd->Uniform(26));
}
return ret;
}
std::string RandomKey(Random* rnd, int len, RandomKeyType type) {
// Make sure to generate a wide variety of characters so we
// test the boundary conditions for short-key optimizations.
static const char kTestChars[] = {
'\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff'
};
std::string result;
for (int i = 0; i < len; i++) {
std::size_t indx = 0;
switch (type) {
case RandomKeyType::RANDOM:
indx = rnd->Uniform(sizeof(kTestChars));
break;
case RandomKeyType::LARGEST:
indx = sizeof(kTestChars) - 1;
break;
case RandomKeyType::MIDDLE:
indx = sizeof(kTestChars) / 2;
break;
case RandomKeyType::SMALLEST:
indx = 0;
break;
}
result += kTestChars[indx];
}
return result;
}
extern Slice CompressibleString(Random* rnd, double compressed_fraction,
int len, std::string* dst) {
int raw = static_cast<int>(len * compressed_fraction);
if (raw < 1) raw = 1;
std::string raw_data;
RandomString(rnd, raw, &raw_data);
// Duplicate the random data until we have filled "len" bytes
dst->clear();
while (dst->size() < (unsigned int)len) {
dst->append(raw_data);
}
dst->resize(len);
return Slice(*dst);
}
namespace {
class Uint64ComparatorImpl : public Comparator {
public:
Uint64ComparatorImpl() { }
virtual const char* Name() const override {
return "rocksdb.Uint64Comparator";
}
virtual int Compare(const Slice& a, const Slice& b) const override {
assert(a.size() == sizeof(uint64_t) && b.size() == sizeof(uint64_t));
const uint64_t* left = reinterpret_cast<const uint64_t*>(a.data());
const uint64_t* right = reinterpret_cast<const uint64_t*>(b.data());
uint64_t leftValue;
uint64_t rightValue;
GetUnaligned(left, &leftValue);
GetUnaligned(right, &rightValue);
if (leftValue == rightValue) {
return 0;
} else if (leftValue < rightValue) {
return -1;
} else {
return 1;
}
}
virtual void FindShortestSeparator(std::string* /*start*/,
const Slice& /*limit*/) const override {
return;
}
virtual void FindShortSuccessor(std::string* /*key*/) const override {
return;
}
};
} // namespace
static port::OnceType once;
static const Comparator* uint64comp;
static void InitModule() {
uint64comp = new Uint64ComparatorImpl;
}
const Comparator* Uint64Comparator() {
port::InitOnce(&once, InitModule);
return uint64comp;
}
WritableFileWriter* GetWritableFileWriter(WritableFile* wf) {
unique_ptr<WritableFile> file(wf);
return new WritableFileWriter(std::move(file), EnvOptions());
}
RandomAccessFileReader* GetRandomAccessFileReader(RandomAccessFile* raf) {
unique_ptr<RandomAccessFile> file(raf);
return new RandomAccessFileReader(std::move(file),
"[test RandomAccessFileReader]");
}
SequentialFileReader* GetSequentialFileReader(SequentialFile* se) {
unique_ptr<SequentialFile> file(se);
return new SequentialFileReader(std::move(file));
}
void CorruptKeyType(InternalKey* ikey) {
std::string keystr = ikey->Encode().ToString();
keystr[keystr.size() - 8] = kTypeLogData;
ikey->DecodeFrom(Slice(keystr.data(), keystr.size()));
}
std::string KeyStr(const std::string& user_key, const SequenceNumber& seq,
const ValueType& t, bool corrupt) {
InternalKey k(user_key, seq, t);
if (corrupt) {
CorruptKeyType(&k);
}
return k.Encode().ToString();
}
std::string RandomName(Random* rnd, const size_t len) {
std::stringstream ss;
for (size_t i = 0; i < len; ++i) {
ss << static_cast<char>(rnd->Uniform(26) + 'a');
}
return ss.str();
}
CompressionType RandomCompressionType(Random* rnd) {
return static_cast<CompressionType>(rnd->Uniform(6));
}
void RandomCompressionTypeVector(const size_t count,
std::vector<CompressionType>* types,
Random* rnd) {
types->clear();
for (size_t i = 0; i < count; ++i) {
types->emplace_back(RandomCompressionType(rnd));
}
}
const SliceTransform* RandomSliceTransform(Random* rnd, int pre_defined) {
int random_num = pre_defined >= 0 ? pre_defined : rnd->Uniform(4);
switch (random_num) {
case 0:
return NewFixedPrefixTransform(rnd->Uniform(20) + 1);
case 1:
return NewCappedPrefixTransform(rnd->Uniform(20) + 1);
case 2:
return NewNoopTransform();
default:
return nullptr;
}
}
BlockBasedTableOptions RandomBlockBasedTableOptions(Random* rnd) {
BlockBasedTableOptions opt;
opt.cache_index_and_filter_blocks = rnd->Uniform(2);
opt.pin_l0_filter_and_index_blocks_in_cache = rnd->Uniform(2);
opt.index_type = rnd->Uniform(2) ? BlockBasedTableOptions::kBinarySearch
: BlockBasedTableOptions::kHashSearch;
opt.hash_index_allow_collision = rnd->Uniform(2);
opt.checksum = static_cast<ChecksumType>(rnd->Uniform(3));
opt.block_size = rnd->Uniform(10000000);
opt.block_size_deviation = rnd->Uniform(100);
opt.block_restart_interval = rnd->Uniform(100);
opt.index_block_restart_interval = rnd->Uniform(100);
opt.whole_key_filtering = rnd->Uniform(2);
return opt;
}
TableFactory* RandomTableFactory(Random* rnd, int pre_defined) {
#ifndef ROCKSDB_LITE
int random_num = pre_defined >= 0 ? pre_defined : rnd->Uniform(4);
switch (random_num) {
case 0:
return NewPlainTableFactory();
case 1:
return NewCuckooTableFactory();
default:
return NewBlockBasedTableFactory();
}
#else
return NewBlockBasedTableFactory();
#endif // !ROCKSDB_LITE
}
MergeOperator* RandomMergeOperator(Random* rnd) {
return new ChanglingMergeOperator(RandomName(rnd, 10));
}
CompactionFilter* RandomCompactionFilter(Random* rnd) {
return new ChanglingCompactionFilter(RandomName(rnd, 10));
}
CompactionFilterFactory* RandomCompactionFilterFactory(Random* rnd) {
return new ChanglingCompactionFilterFactory(RandomName(rnd, 10));
}
void RandomInitDBOptions(DBOptions* db_opt, Random* rnd) {
// boolean options
db_opt->advise_random_on_open = rnd->Uniform(2);
db_opt->allow_mmap_reads = rnd->Uniform(2);
db_opt->allow_mmap_writes = rnd->Uniform(2);
db_opt->use_direct_reads = rnd->Uniform(2);
db_opt->use_direct_io_for_flush_and_compaction = rnd->Uniform(2);
db_opt->create_if_missing = rnd->Uniform(2);
db_opt->create_missing_column_families = rnd->Uniform(2);
db_opt->enable_thread_tracking = rnd->Uniform(2);
db_opt->error_if_exists = rnd->Uniform(2);
db_opt->is_fd_close_on_exec = rnd->Uniform(2);
db_opt->paranoid_checks = rnd->Uniform(2);
db_opt->skip_log_error_on_recovery = rnd->Uniform(2);
db_opt->skip_stats_update_on_db_open = rnd->Uniform(2);
db_opt->use_adaptive_mutex = rnd->Uniform(2);
db_opt->use_fsync = rnd->Uniform(2);
db_opt->recycle_log_file_num = rnd->Uniform(2);
db_opt->avoid_flush_during_recovery = rnd->Uniform(2);
db_opt->avoid_flush_during_shutdown = rnd->Uniform(2);
// int options
db_opt->max_background_compactions = rnd->Uniform(100);
db_opt->max_background_flushes = rnd->Uniform(100);
db_opt->max_file_opening_threads = rnd->Uniform(100);
db_opt->max_open_files = rnd->Uniform(100);
db_opt->table_cache_numshardbits = rnd->Uniform(100);
// size_t options
db_opt->db_write_buffer_size = rnd->Uniform(10000);
db_opt->keep_log_file_num = rnd->Uniform(10000);
db_opt->log_file_time_to_roll = rnd->Uniform(10000);
db_opt->manifest_preallocation_size = rnd->Uniform(10000);
db_opt->max_log_file_size = rnd->Uniform(10000);
// std::string options
db_opt->db_log_dir = "path/to/db_log_dir";
db_opt->wal_dir = "path/to/wal_dir";
// uint32_t options
db_opt->max_subcompactions = rnd->Uniform(100000);
// uint64_t options
static const uint64_t uint_max = static_cast<uint64_t>(UINT_MAX);
db_opt->WAL_size_limit_MB = uint_max + rnd->Uniform(100000);
db_opt->WAL_ttl_seconds = uint_max + rnd->Uniform(100000);
db_opt->bytes_per_sync = uint_max + rnd->Uniform(100000);
db_opt->delayed_write_rate = uint_max + rnd->Uniform(100000);
db_opt->delete_obsolete_files_period_micros = uint_max + rnd->Uniform(100000);
db_opt->max_manifest_file_size = uint_max + rnd->Uniform(100000);
db_opt->max_total_wal_size = uint_max + rnd->Uniform(100000);
db_opt->wal_bytes_per_sync = uint_max + rnd->Uniform(100000);
// unsigned int options
db_opt->stats_dump_period_sec = rnd->Uniform(100000);
}
void RandomInitCFOptions(ColumnFamilyOptions* cf_opt, Random* rnd) {
cf_opt->compaction_style = (CompactionStyle)(rnd->Uniform(4));
// boolean options
cf_opt->report_bg_io_stats = rnd->Uniform(2);
cf_opt->disable_auto_compactions = rnd->Uniform(2);
cf_opt->inplace_update_support = rnd->Uniform(2);
cf_opt->level_compaction_dynamic_level_bytes = rnd->Uniform(2);
cf_opt->optimize_filters_for_hits = rnd->Uniform(2);
cf_opt->paranoid_file_checks = rnd->Uniform(2);
cf_opt->purge_redundant_kvs_while_flush = rnd->Uniform(2);
cf_opt->force_consistency_checks = rnd->Uniform(2);
cf_opt->compaction_options_fifo.allow_compaction = rnd->Uniform(2);
// double options
cf_opt->hard_rate_limit = static_cast<double>(rnd->Uniform(10000)) / 13;
cf_opt->soft_rate_limit = static_cast<double>(rnd->Uniform(10000)) / 13;
cf_opt->memtable_prefix_bloom_size_ratio =
static_cast<double>(rnd->Uniform(10000)) / 20000.0;
// int options
cf_opt->level0_file_num_compaction_trigger = rnd->Uniform(100);
cf_opt->level0_slowdown_writes_trigger = rnd->Uniform(100);
cf_opt->level0_stop_writes_trigger = rnd->Uniform(100);
cf_opt->max_bytes_for_level_multiplier = rnd->Uniform(100);
cf_opt->max_mem_compaction_level = rnd->Uniform(100);
cf_opt->max_write_buffer_number = rnd->Uniform(100);
cf_opt->max_write_buffer_number_to_maintain = rnd->Uniform(100);
cf_opt->min_write_buffer_number_to_merge = rnd->Uniform(100);
cf_opt->num_levels = rnd->Uniform(100);
cf_opt->target_file_size_multiplier = rnd->Uniform(100);
// vector int options
cf_opt->max_bytes_for_level_multiplier_additional.resize(cf_opt->num_levels);
for (int i = 0; i < cf_opt->num_levels; i++) {
cf_opt->max_bytes_for_level_multiplier_additional[i] = rnd->Uniform(100);
}
// size_t options
cf_opt->arena_block_size = rnd->Uniform(10000);
cf_opt->inplace_update_num_locks = rnd->Uniform(10000);
cf_opt->max_successive_merges = rnd->Uniform(10000);
cf_opt->memtable_huge_page_size = rnd->Uniform(10000);
cf_opt->write_buffer_size = rnd->Uniform(10000);
// uint32_t options
cf_opt->bloom_locality = rnd->Uniform(10000);
cf_opt->max_bytes_for_level_base = rnd->Uniform(10000);
// uint64_t options
static const uint64_t uint_max = static_cast<uint64_t>(UINT_MAX);
cf_opt->ttl = uint_max + rnd->Uniform(10000);
cf_opt->max_sequential_skip_in_iterations = uint_max + rnd->Uniform(10000);
cf_opt->target_file_size_base = uint_max + rnd->Uniform(10000);
cf_opt->max_compaction_bytes =
cf_opt->target_file_size_base * rnd->Uniform(100);
cf_opt->compaction_options_fifo.max_table_files_size =
uint_max + rnd->Uniform(10000);
cf_opt->compaction_options_fifo.ttl = uint_max + rnd->Uniform(10000);
// unsigned int options
cf_opt->rate_limit_delay_max_milliseconds = rnd->Uniform(10000);
// pointer typed options
cf_opt->prefix_extractor.reset(RandomSliceTransform(rnd));
cf_opt->table_factory.reset(RandomTableFactory(rnd));
cf_opt->merge_operator.reset(RandomMergeOperator(rnd));
if (cf_opt->compaction_filter) {
delete cf_opt->compaction_filter;
}
cf_opt->compaction_filter = RandomCompactionFilter(rnd);
cf_opt->compaction_filter_factory.reset(RandomCompactionFilterFactory(rnd));
// custom typed options
cf_opt->compression = RandomCompressionType(rnd);
RandomCompressionTypeVector(cf_opt->num_levels,
&cf_opt->compression_per_level, rnd);
}
Status DestroyDir(Env* env, const std::string& dir) {
Status s;
if (env->FileExists(dir).IsNotFound()) {
return s;
}
std::vector<std::string> files_in_dir;
s = env->GetChildren(dir, &files_in_dir);
if (s.ok()) {
for (auto& file_in_dir : files_in_dir) {
if (file_in_dir == "." || file_in_dir == "..") {
continue;
}
s = env->DeleteFile(dir + "/" + file_in_dir);
if (!s.ok()) {
break;
}
}
}
if (s.ok()) {
s = env->DeleteDir(dir);
}
return s;
}
} // namespace test
} // namespace rocksdb