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rocksdb/tools/db_stress.cc

1539 lines
49 KiB

// 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.
//
// 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.
//
// The test uses an array to compare against values written to the database.
// Keys written to the array are in 1:1 correspondence to the actual values in
// the database according to the formula in the function GenerateValue.
// Space is reserved in the array from 0 to FLAGS_max_key and values are
// randomly written/deleted/read from those positions. During verification we
// compare all the positions in the array. To shorten/elongate the running
// time, you could change the settings: FLAGS_max_key, FLAGS_ops_per_thread,
// (sometimes also FLAGS_threads).
//
// NOTE that if FLAGS_test_batches_snapshots is set, the test will have
// different behavior. See comment of the flag for details.
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <gflags/gflags.h>
#include "db/db_impl.h"
#include "db/version_set.h"
#include "rocksdb/statistics.h"
#include "rocksdb/cache.h"
#include "utilities/utility_db.h"
#include "rocksdb/env.h"
#include "rocksdb/write_batch.h"
#include "rocksdb/statistics.h"
#include "port/port.h"
#include "util/coding.h"
#include "util/crc32c.h"
#include "util/histogram.h"
#include "util/mutexlock.h"
#include "util/random.h"
#include "util/testutil.h"
#include "util/logging.h"
#include "utilities/ttl/db_ttl.h"
#include "hdfs/env_hdfs.h"
#include "utilities/merge_operators.h"
static const long KB = 1024;
static bool ValidateUint32Range(const char* flagname, uint64_t value) {
if (value > std::numeric_limits<uint32_t>::max()) {
fprintf(stderr,
"Invalid value for --%s: %lu, overflow\n",
flagname,
(unsigned long)value);
return false;
}
return true;
}
DEFINE_uint64(seed, 2341234, "Seed for PRNG");
static const bool FLAGS_seed_dummy =
google::RegisterFlagValidator(&FLAGS_seed, &ValidateUint32Range);
DEFINE_int64(max_key, 1 * KB * KB * KB,
"Max number of key/values to place in database");
DEFINE_bool(test_batches_snapshots, false,
"If set, the test uses MultiGet(), MultiPut() and MultiDelete()"
" which read/write/delete multiple keys in a batch. In this mode,"
" we do not verify db content by comparing the content with the "
"pre-allocated array. Instead, we do partial verification inside"
" MultiGet() by checking various values in a batch. Benefit of"
" this mode:\n"
"\t(a) No need to acquire mutexes during writes (less cache "
"flushes in multi-core leading to speed up)\n"
"\t(b) No long validation at the end (more speed up)\n"
"\t(c) Test snapshot and atomicity of batch writes");
DEFINE_int32(threads, 32, "Number of concurrent threads to run.");
DEFINE_int32(ttl, -1,
"Opens the db with this ttl value if this is not -1. "
"Carefully specify a large value such that verifications on "
"deleted values don't fail");
DEFINE_int32(value_size_mult, 8,
"Size of value will be this number times rand_int(1,3) bytes");
DEFINE_bool(verify_before_write, false, "Verify before write");
DEFINE_bool(histogram, false, "Print histogram of operation timings");
DEFINE_bool(destroy_db_initially, true,
"Destroys the database dir before start if this is true");
DEFINE_bool (verbose, false, "Verbose");
DEFINE_int32(write_buffer_size, rocksdb::Options().write_buffer_size,
"Number of bytes to buffer in memtable before compacting");
DEFINE_int32(max_write_buffer_number,
rocksdb::Options().max_write_buffer_number,
"The number of in-memory memtables. "
"Each memtable is of size FLAGS_write_buffer_size.");
DEFINE_int32(min_write_buffer_number_to_merge,
rocksdb::Options().min_write_buffer_number_to_merge,
"The minimum number of write buffers that will be merged together "
"before writing to storage. This is cheap because it is an "
"in-memory merge. If this feature is not enabled, then all these "
"write buffers are flushed to L0 as separate files and this "
"increases read amplification because a get request has to check "
"in all of these files. Also, an in-memory merge may result in "
"writing less data to storage if there are duplicate records in"
" each of these individual write buffers.");
DEFINE_int32(open_files, rocksdb::Options().max_open_files,
"Maximum number of files to keep open at the same time "
"(use default if == 0)");
DEFINE_int64(compressed_cache_size, -1,
"Number of bytes to use as a cache of compressed data."
" Negative means use default settings.");
DEFINE_int32(compaction_style, rocksdb::Options().compaction_style, "");
DEFINE_int32(level0_file_num_compaction_trigger,
rocksdb::Options().level0_file_num_compaction_trigger,
"Level0 compaction start trigger");
DEFINE_int32(level0_slowdown_writes_trigger,
rocksdb::Options().level0_slowdown_writes_trigger,
"Number of files in level-0 that will slow down writes");
DEFINE_int32(level0_stop_writes_trigger,
rocksdb::Options().level0_stop_writes_trigger,
"Number of files in level-0 that will trigger put stop.");
DEFINE_int32(block_size, rocksdb::Options().block_size,
"Number of bytes in a block.");
DEFINE_int32(max_background_compactions,
rocksdb::Options().max_background_compactions,
"The maximum number of concurrent background compactions "
"that can occur in parallel.");
DEFINE_int32(universal_size_ratio, 0, "The ratio of file sizes that trigger"
" compaction in universal style");
DEFINE_int32(universal_min_merge_width, 0, "The minimum number of files to "
"compact in universal style compaction");
DEFINE_int32(universal_max_merge_width, 0, "The max number of files to compact"
" in universal style compaction");
DEFINE_int32(universal_max_size_amplification_percent, 0,
"The max size amplification for universal style compaction");
DEFINE_int64(cache_size, 2 * KB * KB * KB,
"Number of bytes to use as a cache of uncompressed data.");
static bool ValidateInt32Positive(const char* flagname, int32_t value) {
if (value < 0) {
fprintf(stderr, "Invalid value for --%s: %d, must be >=0\n",
flagname, value);
return false;
}
return true;
}
DEFINE_int32(reopen, 10, "Number of times database reopens");
static const bool FLAGS_reopen_dummy =
google::RegisterFlagValidator(&FLAGS_reopen, &ValidateInt32Positive);
DEFINE_int32(bloom_bits, 10, "Bloom filter bits per key. "
"Negative means use default settings.");
DEFINE_string(db, "", "Use the db with the following name.");
DEFINE_bool(verify_checksum, false,
"Verify checksum for every block read from storage");
DEFINE_bool(mmap_read, rocksdb::EnvOptions().use_mmap_reads,
"Allow reads to occur via mmap-ing files");
// Database statistics
static std::shared_ptr<rocksdb::Statistics> dbstats;
DEFINE_bool(statistics, false, "Create database statistics");
DEFINE_bool(sync, false, "Sync all writes to disk");
DEFINE_bool(disable_data_sync, false,
"If true, do not wait until data is synced to disk.");
DEFINE_bool(use_fsync, false, "If true, issue fsync instead of fdatasync");
DEFINE_int32(kill_random_test, 0,
"If non-zero, kill at various points in source code with "
"probability 1/this");
static const bool FLAGS_kill_random_test_dummy =
google::RegisterFlagValidator(&FLAGS_kill_random_test,
&ValidateInt32Positive);
extern int rocksdb_kill_odds;
DEFINE_bool(disable_wal, false, "If true, do not write WAL for write.");
DEFINE_int32(target_file_size_base, 64 * KB,
"Target level-1 file size for compaction");
DEFINE_int32(target_file_size_multiplier, 1,
"A multiplier to compute targe level-N file size (N >= 2)");
DEFINE_uint64(max_bytes_for_level_base, 256 * KB, "Max bytes for level-1");
DEFINE_int32(max_bytes_for_level_multiplier, 2,
"A multiplier to compute max bytes for level-N (N >= 2)");
static bool ValidateInt32Percent(const char* flagname, int32_t value) {
if (value < 0 || value>100) {
fprintf(stderr, "Invalid value for --%s: %d, 0<= pct <=100 \n",
flagname, value);
return false;
}
return true;
}
DEFINE_int32(readpercent, 10,
"Ratio of reads to total workload (expressed as a percentage)");
static const bool FLAGS_readpercent_dummy =
google::RegisterFlagValidator(&FLAGS_readpercent, &ValidateInt32Percent);
DEFINE_int32(prefixpercent, 20,
"Ratio of prefix iterators to total workload (expressed as a"
" percentage)");
static const bool FLAGS_prefixpercent_dummy =
google::RegisterFlagValidator(&FLAGS_prefixpercent, &ValidateInt32Percent);
DEFINE_int32(writepercent, 45,
" Ratio of deletes to total workload (expressed as a percentage)");
static const bool FLAGS_writepercent_dummy =
google::RegisterFlagValidator(&FLAGS_writepercent, &ValidateInt32Percent);
DEFINE_int32(delpercent, 15,
"Ratio of deletes to total workload (expressed as a percentage)");
static const bool FLAGS_delpercent_dummy =
google::RegisterFlagValidator(&FLAGS_delpercent, &ValidateInt32Percent);
DEFINE_int32(iterpercent, 10, "Ratio of iterations to total workload"
" (expressed as a percentage)");
static const bool FLAGS_iterpercent_dummy =
google::RegisterFlagValidator(&FLAGS_iterpercent, &ValidateInt32Percent);
DEFINE_uint64(num_iterations, 10, "Number of iterations per MultiIterate run");
static const bool FLAGS_num_iterations_dummy =
google::RegisterFlagValidator(&FLAGS_num_iterations, &ValidateUint32Range);
DEFINE_bool(disable_seek_compaction, false,
"Option to disable compation triggered by read.");
DEFINE_uint64(delete_obsolete_files_period_micros, 0,
"Option to delete obsolete files periodically"
"0 means that obsolete files are "
" deleted after every compaction run.");
enum rocksdb::CompressionType StringToCompressionType(const char* ctype) {
assert(ctype);
if (!strcasecmp(ctype, "none"))
return rocksdb::kNoCompression;
else if (!strcasecmp(ctype, "snappy"))
return rocksdb::kSnappyCompression;
else if (!strcasecmp(ctype, "zlib"))
return rocksdb::kZlibCompression;
else if (!strcasecmp(ctype, "bzip2"))
return rocksdb::kBZip2Compression;
fprintf(stdout, "Cannot parse compression type '%s'\n", ctype);
return rocksdb::kSnappyCompression; //default value
}
DEFINE_string(compression_type, "snappy",
"Algorithm to use to compress the database");
static enum rocksdb::CompressionType FLAGS_compression_type_e =
rocksdb::kSnappyCompression;
DEFINE_string(hdfs, "", "Name of hdfs environment");
// posix or hdfs environment
static rocksdb::Env* FLAGS_env = rocksdb::Env::Default();
DEFINE_uint64(ops_per_thread, 600000, "Number of operations per thread.");
static const bool FLAGS_ops_per_thread_dummy =
google::RegisterFlagValidator(&FLAGS_ops_per_thread, &ValidateUint32Range);
DEFINE_uint64(log2_keys_per_lock, 2, "Log2 of number of keys per lock");
static const bool FLAGS_log2_keys_per_lock_dummy =
google::RegisterFlagValidator(&FLAGS_log2_keys_per_lock,
&ValidateUint32Range);
DEFINE_int32(purge_redundant_percent, 50,
"Percentage of times we want to purge redundant keys in memory "
"before flushing");
static const bool FLAGS_purge_redundant_percent_dummy =
google::RegisterFlagValidator(&FLAGS_purge_redundant_percent,
&ValidateInt32Percent);
DEFINE_bool(filter_deletes, false, "On true, deletes use KeyMayExist to drop"
" the delete if key not present");
enum RepFactory {
kSkipList,
kHashSkipList,
kVectorRep
};
enum RepFactory StringToRepFactory(const char* ctype) {
assert(ctype);
if (!strcasecmp(ctype, "skip_list"))
return kSkipList;
else if (!strcasecmp(ctype, "prefix_hash"))
return kHashSkipList;
else if (!strcasecmp(ctype, "vector"))
return kVectorRep;
fprintf(stdout, "Cannot parse memreptable %s\n", ctype);
return kSkipList;
}
static enum RepFactory FLAGS_rep_factory;
DEFINE_string(memtablerep, "skip_list", "");
static bool ValidatePrefixSize(const char* flagname, int32_t value) {
if (value < 0 || value>=2000000000) {
fprintf(stderr, "Invalid value for --%s: %d. 0<= PrefixSize <=2000000000\n",
flagname, value);
return false;
}
return true;
}
DEFINE_int32(prefix_size, 0, "Control the prefix size for HashSkipListRep");
static const bool FLAGS_prefix_size_dummy =
google::RegisterFlagValidator(&FLAGS_prefix_size, &ValidatePrefixSize);
DEFINE_bool(use_merge, false, "On true, replaces all writes with a Merge "
"that behaves like a Put");
namespace rocksdb {
// convert long to a big-endian slice key
static std::string Key(long val) {
std::string little_endian_key;
std::string big_endian_key;
PutFixed64(&little_endian_key, val);
assert(little_endian_key.size() == sizeof(val));
big_endian_key.resize(sizeof(val));
for (int i=0; i<(int)sizeof(val); i++) {
big_endian_key[i] = little_endian_key[sizeof(val) - 1 - i];
}
return big_endian_key;
}
class StressTest;
namespace {
class Stats {
private:
double start_;
double finish_;
double seconds_;
long done_;
long gets_;
long prefixes_;
long writes_;
long deletes_;
long iterator_size_sums_;
long founds_;
long iterations_;
long errors_;
int next_report_;
size_t bytes_;
double last_op_finish_;
HistogramImpl hist_;
public:
Stats() { }
void Start() {
next_report_ = 100;
hist_.Clear();
done_ = 0;
gets_ = 0;
prefixes_ = 0;
writes_ = 0;
deletes_ = 0;
iterator_size_sums_ = 0;
founds_ = 0;
iterations_ = 0;
errors_ = 0;
bytes_ = 0;
seconds_ = 0;
start_ = FLAGS_env->NowMicros();
last_op_finish_ = start_;
finish_ = start_;
}
void Merge(const Stats& other) {
hist_.Merge(other.hist_);
done_ += other.done_;
gets_ += other.gets_;
prefixes_ += other.prefixes_;
writes_ += other.writes_;
deletes_ += other.deletes_;
iterator_size_sums_ += other.iterator_size_sums_;
founds_ += other.founds_;
iterations_ += other.iterations_;
errors_ += other.errors_;
bytes_ += other.bytes_;
seconds_ += other.seconds_;
if (other.start_ < start_) start_ = other.start_;
if (other.finish_ > finish_) finish_ = other.finish_;
}
void Stop() {
finish_ = FLAGS_env->NowMicros();
seconds_ = (finish_ - start_) * 1e-6;
}
void FinishedSingleOp() {
if (FLAGS_histogram) {
double now = FLAGS_env->NowMicros();
double micros = now - last_op_finish_;
hist_.Add(micros);
if (micros > 20000) {
fprintf(stdout, "long op: %.1f micros%30s\r", micros, "");
}
last_op_finish_ = now;
}
done_++;
if (done_ >= next_report_) {
if (next_report_ < 1000) next_report_ += 100;
else if (next_report_ < 5000) next_report_ += 500;
else if (next_report_ < 10000) next_report_ += 1000;
else if (next_report_ < 50000) next_report_ += 5000;
else if (next_report_ < 100000) next_report_ += 10000;
else if (next_report_ < 500000) next_report_ += 50000;
else next_report_ += 100000;
fprintf(stdout, "... finished %ld ops%30s\r", done_, "");
}
}
void AddBytesForWrites(int nwrites, size_t nbytes) {
writes_ += nwrites;
bytes_ += nbytes;
}
void AddGets(int ngets, int nfounds) {
founds_ += nfounds;
gets_ += ngets;
}
void AddPrefixes(int nprefixes, int count) {
prefixes_ += nprefixes;
iterator_size_sums_ += count;
}
void AddIterations(int n) {
iterations_ += n;
}
void AddDeletes(int n) {
deletes_ += n;
}
void AddErrors(int n) {
errors_ += n;
}
void Report(const char* name) {
std::string extra;
if (bytes_ < 1 || done_ < 1) {
fprintf(stderr, "No writes or ops?\n");
return;
}
double elapsed = (finish_ - start_) * 1e-6;
double bytes_mb = bytes_ / 1048576.0;
double rate = bytes_mb / elapsed;
double throughput = (double)done_/elapsed;
fprintf(stdout, "%-12s: ", name);
fprintf(stdout, "%.3f micros/op %ld ops/sec\n",
seconds_ * 1e6 / done_, (long)throughput);
fprintf(stdout, "%-12s: Wrote %.2f MB (%.2f MB/sec) (%ld%% of %ld ops)\n",
"", bytes_mb, rate, (100*writes_)/done_, done_);
fprintf(stdout, "%-12s: Wrote %ld times\n", "", writes_);
fprintf(stdout, "%-12s: Deleted %ld times\n", "", deletes_);
fprintf(stdout, "%-12s: %ld read and %ld found the key\n", "",
gets_, founds_);
fprintf(stdout, "%-12s: Prefix scanned %ld times\n", "", prefixes_);
fprintf(stdout, "%-12s: Iterator size sum is %ld\n", "",
iterator_size_sums_);
fprintf(stdout, "%-12s: Iterated %ld times\n", "", iterations_);
fprintf(stdout, "%-12s: Got errors %ld times\n", "", errors_);
if (FLAGS_histogram) {
fprintf(stdout, "Microseconds per op:\n%s\n", hist_.ToString().c_str());
}
fflush(stdout);
}
};
// State shared by all concurrent executions of the same benchmark.
class SharedState {
public:
static const uint32_t SENTINEL = 0xffffffff;
explicit SharedState(StressTest* stress_test) :
cv_(&mu_),
seed_(FLAGS_seed),
max_key_(FLAGS_max_key),
log2_keys_per_lock_(FLAGS_log2_keys_per_lock),
num_threads_(FLAGS_threads),
num_initialized_(0),
num_populated_(0),
vote_reopen_(0),
num_done_(0),
start_(false),
start_verify_(false),
stress_test_(stress_test) {
if (FLAGS_test_batches_snapshots) {
key_locks_ = nullptr;
values_ = nullptr;
fprintf(stdout, "No lock creation because test_batches_snapshots set\n");
return;
}
values_ = new uint32_t[max_key_];
for (long i = 0; i < max_key_; i++) {
values_[i] = SENTINEL;
}
long num_locks = (max_key_ >> log2_keys_per_lock_);
if (max_key_ & ((1 << log2_keys_per_lock_) - 1)) {
num_locks ++;
}
fprintf(stdout, "Creating %ld locks\n", num_locks);
key_locks_ = new port::Mutex[num_locks];
}
~SharedState() {
delete[] values_;
delete[] key_locks_;
}
port::Mutex* GetMutex() {
return &mu_;
}
port::CondVar* GetCondVar() {
return &cv_;
}
StressTest* GetStressTest() const {
return stress_test_;
}
long GetMaxKey() const {
return max_key_;
}
uint32_t GetNumThreads() const {
return num_threads_;
}
void IncInitialized() {
num_initialized_++;
}
void IncOperated() {
num_populated_++;
}
void IncDone() {
num_done_++;
}
void IncVotedReopen() {
vote_reopen_ = (vote_reopen_ + 1) % num_threads_;
}
bool AllInitialized() const {
return num_initialized_ >= num_threads_;
}
bool AllOperated() const {
return num_populated_ >= num_threads_;
}
bool AllDone() const {
return num_done_ >= num_threads_;
}
bool AllVotedReopen() {
return (vote_reopen_ == 0);
}
void SetStart() {
start_ = true;
}
void SetStartVerify() {
start_verify_ = true;
}
bool Started() const {
return start_;
}
bool VerifyStarted() const {
return start_verify_;
}
port::Mutex* GetMutexForKey(long key) {
return &key_locks_[key >> log2_keys_per_lock_];
}
void Put(long key, uint32_t value_base) {
values_[key] = value_base;
}
uint32_t Get(long key) const {
return values_[key];
}
void Delete(long key) const {
values_[key] = SENTINEL;
}
uint32_t GetSeed() const {
return seed_;
}
private:
port::Mutex mu_;
port::CondVar cv_;
const uint32_t seed_;
const long max_key_;
const uint32_t log2_keys_per_lock_;
const int num_threads_;
long num_initialized_;
long num_populated_;
long vote_reopen_;
long num_done_;
bool start_;
bool start_verify_;
StressTest* stress_test_;
uint32_t *values_;
port::Mutex *key_locks_;
};
// Per-thread state for concurrent executions of the same benchmark.
struct ThreadState {
uint32_t tid; // 0..n-1
Random rand; // Has different seeds for different threads
SharedState* shared;
Stats stats;
ThreadState(uint32_t index, SharedState *shared)
: tid(index),
rand(1000 + index + shared->GetSeed()),
shared(shared) {
}
};
} // namespace
class StressTest {
public:
StressTest()
: cache_(NewLRUCache(FLAGS_cache_size)),
compressed_cache_(FLAGS_compressed_cache_size >= 0 ?
NewLRUCache(FLAGS_compressed_cache_size) :
nullptr),
filter_policy_(FLAGS_bloom_bits >= 0
? NewBloomFilterPolicy(FLAGS_bloom_bits)
: nullptr),
prefix_extractor_(NewFixedPrefixTransform(
FLAGS_test_batches_snapshots ?
sizeof(long) : sizeof(long)-1)),
db_(nullptr),
num_times_reopened_(0) {
if (FLAGS_destroy_db_initially) {
std::vector<std::string> files;
FLAGS_env->GetChildren(FLAGS_db, &files);
for (unsigned int i = 0; i < files.size(); i++) {
if (Slice(files[i]).starts_with("heap-")) {
FLAGS_env->DeleteFile(FLAGS_db + "/" + files[i]);
}
}
DestroyDB(FLAGS_db, Options());
}
}
~StressTest() {
delete db_;
delete filter_policy_;
delete prefix_extractor_;
}
void Run() {
PrintEnv();
Open();
SharedState shared(this);
uint32_t n = shared.GetNumThreads();
std::vector<ThreadState*> threads(n);
for (uint32_t i = 0; i < n; i++) {
threads[i] = new ThreadState(i, &shared);
FLAGS_env->StartThread(ThreadBody, threads[i]);
}
// Each thread goes through the following states:
// initializing -> wait for others to init -> read/populate/depopulate
// wait for others to operate -> verify -> done
{
MutexLock l(shared.GetMutex());
while (!shared.AllInitialized()) {
shared.GetCondVar()->Wait();
}
double now = FLAGS_env->NowMicros();
fprintf(stdout, "%s Starting database operations\n",
FLAGS_env->TimeToString((uint64_t) now/1000000).c_str());
shared.SetStart();
shared.GetCondVar()->SignalAll();
while (!shared.AllOperated()) {
shared.GetCondVar()->Wait();
}
now = FLAGS_env->NowMicros();
if (FLAGS_test_batches_snapshots) {
fprintf(stdout, "%s Limited verification already done during gets\n",
FLAGS_env->TimeToString((uint64_t) now/1000000).c_str());
} else {
fprintf(stdout, "%s Starting verification\n",
FLAGS_env->TimeToString((uint64_t) now/1000000).c_str());
}
shared.SetStartVerify();
shared.GetCondVar()->SignalAll();
while (!shared.AllDone()) {
shared.GetCondVar()->Wait();
}
}
for (unsigned int i = 1; i < n; i++) {
threads[0]->stats.Merge(threads[i]->stats);
}
threads[0]->stats.Report("Stress Test");
for (unsigned int i = 0; i < n; i++) {
delete threads[i];
threads[i] = nullptr;
}
double now = FLAGS_env->NowMicros();
if (!FLAGS_test_batches_snapshots) {
fprintf(stdout, "%s Verification successful\n",
FLAGS_env->TimeToString((uint64_t) now/1000000).c_str());
}
PrintStatistics();
}
private:
static void ThreadBody(void* v) {
ThreadState* thread = reinterpret_cast<ThreadState*>(v);
SharedState* shared = thread->shared;
{
MutexLock l(shared->GetMutex());
shared->IncInitialized();
if (shared->AllInitialized()) {
shared->GetCondVar()->SignalAll();
}
while (!shared->Started()) {
shared->GetCondVar()->Wait();
}
}
thread->shared->GetStressTest()->OperateDb(thread);
{
MutexLock l(shared->GetMutex());
shared->IncOperated();
if (shared->AllOperated()) {
shared->GetCondVar()->SignalAll();
}
while (!shared->VerifyStarted()) {
shared->GetCondVar()->Wait();
}
}
if (!FLAGS_test_batches_snapshots) {
thread->shared->GetStressTest()->VerifyDb(thread);
}
{
MutexLock l(shared->GetMutex());
shared->IncDone();
if (shared->AllDone()) {
shared->GetCondVar()->SignalAll();
}
}
}
// Given a key K and value V, this puts ("0"+K, "0"+V), ("1"+K, "1"+V), ...
// ("9"+K, "9"+V) in DB atomically i.e in a single batch.
// Also refer MultiGet.
Status MultiPut(ThreadState* thread,
const WriteOptions& writeoptions,
const Slice& key, const Slice& value, size_t sz) {
std::string keys[10] = {"9", "8", "7", "6", "5",
"4", "3", "2", "1", "0"};
std::string values[10] = {"9", "8", "7", "6", "5",
"4", "3", "2", "1", "0"};
Slice value_slices[10];
WriteBatch batch;
Status s;
for (int i = 0; i < 10; i++) {
keys[i] += key.ToString();
values[i] += value.ToString();
value_slices[i] = values[i];
if (FLAGS_use_merge) {
batch.Merge(keys[i], value_slices[i]);
} else {
batch.Put(keys[i], value_slices[i]);
}
}
s = db_->Write(writeoptions, &batch);
if (!s.ok()) {
fprintf(stderr, "multiput error: %s\n", s.ToString().c_str());
thread->stats.AddErrors(1);
} else {
// we did 10 writes each of size sz + 1
thread->stats.AddBytesForWrites(10, (sz + 1) * 10);
}
return s;
}
// Given a key K, this deletes ("0"+K), ("1"+K),... ("9"+K)
// in DB atomically i.e in a single batch. Also refer MultiGet.
Status MultiDelete(ThreadState* thread,
const WriteOptions& writeoptions,
const Slice& key) {
std::string keys[10] = {"9", "7", "5", "3", "1",
"8", "6", "4", "2", "0"};
WriteBatch batch;
Status s;
for (int i = 0; i < 10; i++) {
keys[i] += key.ToString();
batch.Delete(keys[i]);
}
s = db_->Write(writeoptions, &batch);
if (!s.ok()) {
fprintf(stderr, "multidelete error: %s\n", s.ToString().c_str());
thread->stats.AddErrors(1);
} else {
thread->stats.AddDeletes(10);
}
return s;
}
// Given a key K, this gets values for "0"+K, "1"+K,..."9"+K
// in the same snapshot, and verifies that all the values are of the form
// "0"+V, "1"+V,..."9"+V.
// ASSUMES that MultiPut was used to put (K, V) into the DB.
Status MultiGet(ThreadState* thread,
const ReadOptions& readoptions,
const Slice& key, std::string* value) {
std::string keys[10] = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"};
Slice key_slices[10];
std::string values[10];
ReadOptions readoptionscopy = readoptions;
readoptionscopy.snapshot = db_->GetSnapshot();
Status s;
for (int i = 0; i < 10; i++) {
keys[i] += key.ToString();
key_slices[i] = keys[i];
s = db_->Get(readoptionscopy, key_slices[i], value);
if (!s.ok() && !s.IsNotFound()) {
fprintf(stderr, "get error: %s\n", s.ToString().c_str());
values[i] = "";
thread->stats.AddErrors(1);
// we continue after error rather than exiting so that we can
// find more errors if any
} else if (s.IsNotFound()) {
values[i] = "";
thread->stats.AddGets(1, 0);
} else {
values[i] = *value;
char expected_prefix = (keys[i])[0];
char actual_prefix = (values[i])[0];
if (actual_prefix != expected_prefix) {
fprintf(stderr, "error expected prefix = %c actual = %c\n",
expected_prefix, actual_prefix);
}
(values[i])[0] = ' '; // blank out the differing character
thread->stats.AddGets(1, 1);
}
}
db_->ReleaseSnapshot(readoptionscopy.snapshot);
// Now that we retrieved all values, check that they all match
for (int i = 1; i < 10; i++) {
if (values[i] != values[0]) {
fprintf(stderr, "error : inconsistent values for key %s: %s, %s\n",
key.ToString().c_str(), values[0].c_str(),
values[i].c_str());
// we continue after error rather than exiting so that we can
// find more errors if any
}
}
return s;
}
// Given a prefix P, this does prefix scans for "0"+P, "1"+P,..."9"+P
// in the same snapshot. Each of these 10 scans returns a series of
// values; each series should be the same length, and it is verified
// for each index i that all the i'th values are of the form "0"+V,
// "1"+V,..."9"+V.
// ASSUMES that MultiPut was used to put (K, V)
Status MultiPrefixScan(ThreadState* thread,
const ReadOptions& readoptions,
const Slice& prefix) {
std::string prefixes[10] = {"0", "1", "2", "3", "4",
"5", "6", "7", "8", "9"};
Slice prefix_slices[10];
ReadOptions readoptionscopy[10];
const Snapshot* snapshot = db_->GetSnapshot();
Iterator* iters[10];
Status s = Status::OK();
for (int i = 0; i < 10; i++) {
prefixes[i] += prefix.ToString();
prefix_slices[i] = prefixes[i];
readoptionscopy[i] = readoptions;
readoptionscopy[i].prefix = &prefix_slices[i];
readoptionscopy[i].snapshot = snapshot;
iters[i] = db_->NewIterator(readoptionscopy[i]);
iters[i]->SeekToFirst();
}
int count = 0;
while (iters[0]->Valid()) {
count++;
std::string values[10];
// get list of all values for this iteration
for (int i = 0; i < 10; i++) {
// no iterator should finish before the first one
assert(iters[i]->Valid());
values[i] = iters[i]->value().ToString();
char expected_first = (prefixes[i])[0];
char actual_first = (values[i])[0];
if (actual_first != expected_first) {
fprintf(stderr, "error expected first = %c actual = %c\n",
expected_first, actual_first);
}
(values[i])[0] = ' '; // blank out the differing character
}
// make sure all values are equivalent
for (int i = 0; i < 10; i++) {
if (values[i] != values[0]) {
fprintf(stderr, "error : inconsistent values for prefix %s: %s, %s\n",
prefix.ToString().c_str(), values[0].c_str(),
values[i].c_str());
// we continue after error rather than exiting so that we can
// find more errors if any
}
iters[i]->Next();
}
}
// cleanup iterators and snapshot
for (int i = 0; i < 10; i++) {
// if the first iterator finished, they should have all finished
assert(!iters[i]->Valid());
assert(iters[i]->status().ok());
delete iters[i];
}
db_->ReleaseSnapshot(snapshot);
if (s.ok()) {
thread->stats.AddPrefixes(1, count);
} else {
thread->stats.AddErrors(1);
}
return s;
}
// Given a key K, this creates an iterator which scans to K and then
// does a random sequence of Next/Prev operations.
Status MultiIterate(ThreadState* thread,
const ReadOptions& readoptions,
const Slice& key) {
Status s;
const Snapshot* snapshot = db_->GetSnapshot();
ReadOptions readoptionscopy = readoptions;
readoptionscopy.snapshot = snapshot;
unique_ptr<Iterator> iter(db_->NewIterator(readoptionscopy));
iter->Seek(key);
for (uint64_t i = 0; i < FLAGS_num_iterations && iter->Valid(); i++) {
if (thread->rand.OneIn(2)) {
iter->Next();
} else {
iter->Prev();
}
}
if (s.ok()) {
thread->stats.AddIterations(1);
} else {
thread->stats.AddErrors(1);
}
db_->ReleaseSnapshot(snapshot);
return s;
}
void OperateDb(ThreadState* thread) {
ReadOptions read_opts(FLAGS_verify_checksum, true);
WriteOptions write_opts;
char value[100];
long max_key = thread->shared->GetMaxKey();
std::string from_db;
if (FLAGS_sync) {
write_opts.sync = true;
}
write_opts.disableWAL = FLAGS_disable_wal;
const int prefixBound = (int)FLAGS_readpercent + (int)FLAGS_prefixpercent;
const int writeBound = prefixBound + (int)FLAGS_writepercent;
const int delBound = writeBound + (int)FLAGS_delpercent;
thread->stats.Start();
for (uint64_t i = 0; i < FLAGS_ops_per_thread; i++) {
if(i != 0 && (i % (FLAGS_ops_per_thread / (FLAGS_reopen + 1))) == 0) {
{
thread->stats.FinishedSingleOp();
MutexLock l(thread->shared->GetMutex());
thread->shared->IncVotedReopen();
if (thread->shared->AllVotedReopen()) {
thread->shared->GetStressTest()->Reopen();
thread->shared->GetCondVar()->SignalAll();
}
else {
thread->shared->GetCondVar()->Wait();
}
// Commenting this out as we don't want to reset stats on each open.
// thread->stats.Start();
}
}
long rand_key = thread->rand.Next() % max_key;
std::string keystr = Key(rand_key);
Slice key = keystr;
int prob_op = thread->rand.Uniform(100);
if (prob_op >= 0 && prob_op < (int)FLAGS_readpercent) {
// OPERATION read
if (!FLAGS_test_batches_snapshots) {
Status s = db_->Get(read_opts, key, &from_db);
if (s.ok()) {
// found case
thread->stats.AddGets(1, 1);
} else if (s.IsNotFound()) {
// not found case
thread->stats.AddGets(1, 0);
} else {
// errors case
thread->stats.AddErrors(1);
}
} else {
MultiGet(thread, read_opts, key, &from_db);
}
} else if ((int)FLAGS_readpercent <= prob_op && prob_op < prefixBound) {
// OPERATION prefix scan
// keys are longs (e.g., 8 bytes), so we let prefixes be
// everything except the last byte. So there will be 2^8=256
// keys per prefix.
Slice prefix = Slice(key.data(), key.size() - 1);
if (!FLAGS_test_batches_snapshots) {
read_opts.prefix = &prefix;
Iterator* iter = db_->NewIterator(read_opts);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
assert(iter->key().starts_with(prefix));
count++;
}
assert(count <= 256);
if (iter->status().ok()) {
thread->stats.AddPrefixes(1, count);
} else {
thread->stats.AddErrors(1);
}
delete iter;
} else {
MultiPrefixScan(thread, read_opts, prefix);
}
read_opts.prefix = nullptr;
} else if (prefixBound <= prob_op && prob_op < writeBound) {
// OPERATION write
uint32_t value_base = thread->rand.Next();
size_t sz = GenerateValue(value_base, value, sizeof(value));
Slice v(value, sz);
if (!FLAGS_test_batches_snapshots) {
MutexLock l(thread->shared->GetMutexForKey(rand_key));
if (FLAGS_verify_before_write) {
std::string keystr2 = Key(rand_key);
Slice k = keystr2;
Status s = db_->Get(read_opts, k, &from_db);
VerifyValue(rand_key,
read_opts,
*(thread->shared),
from_db,
s,
true);
}
thread->shared->Put(rand_key, value_base);
if (FLAGS_use_merge) {
db_->Merge(write_opts, key, v);
} else {
db_->Put(write_opts, key, v);
}
thread->stats.AddBytesForWrites(1, sz);
} else {
MultiPut(thread, write_opts, key, v, sz);
}
PrintKeyValue(rand_key, value, sz);
} else if (writeBound <= prob_op && prob_op < delBound) {
// OPERATION delete
if (!FLAGS_test_batches_snapshots) {
MutexLock l(thread->shared->GetMutexForKey(rand_key));
thread->shared->Delete(rand_key);
db_->Delete(write_opts, key);
thread->stats.AddDeletes(1);
} else {
MultiDelete(thread, write_opts, key);
}
} else {
// OPERATION iterate
MultiIterate(thread, read_opts, key);
}
thread->stats.FinishedSingleOp();
}
thread->stats.Stop();
}
void VerifyDb(ThreadState* thread) const {
ReadOptions options(FLAGS_verify_checksum, true);
const SharedState& shared = *(thread->shared);
static const long max_key = shared.GetMaxKey();
static const long keys_per_thread = max_key / shared.GetNumThreads();
long start = keys_per_thread * thread->tid;
long end = start + keys_per_thread;
if (thread->tid == shared.GetNumThreads() - 1) {
end = max_key;
}
if (!thread->rand.OneIn(2)) {
// Use iterator to verify this range
unique_ptr<Iterator> iter(db_->NewIterator(options));
iter->Seek(Key(start));
for (long i = start; i < end; i++) {
std::string from_db;
std::string keystr = Key(i);
Slice k = keystr;
Status s = iter->status();
if (iter->Valid()) {
if (iter->key().compare(k) > 0) {
s = Status::NotFound(Slice());
} else if (iter->key().compare(k) == 0) {
from_db = iter->value().ToString();
iter->Next();
} else if (iter->key().compare(k) < 0) {
VerificationAbort("An out of range key was found", i);
}
} else {
// The iterator found no value for the key in question, so do not
// move to the next item in the iterator
s = Status::NotFound(Slice());
}
VerifyValue(i, options, shared, from_db, s, true);
if (from_db.length()) {
PrintKeyValue(i, from_db.data(), from_db.length());
}
}
}
else {
// Use Get to verify this range
for (long i = start; i < end; i++) {
std::string from_db;
std::string keystr = Key(i);
Slice k = keystr;
Status s = db_->Get(options, k, &from_db);
VerifyValue(i, options, shared, from_db, s, true);
if (from_db.length()) {
PrintKeyValue(i, from_db.data(), from_db.length());
}
}
}
}
void VerificationAbort(std::string msg, long key) const {
fprintf(stderr, "Verification failed for key %ld: %s\n",
key, msg.c_str());
exit(1);
}
void VerifyValue(long key,
const ReadOptions &opts,
const SharedState &shared,
const std::string &value_from_db,
Status s,
bool strict=false) const {
// compare value_from_db with the value in the shared state
char value[100];
uint32_t value_base = shared.Get(key);
if (value_base == SharedState::SENTINEL && !strict) {
return;
}
if (s.ok()) {
if (value_base == SharedState::SENTINEL) {
VerificationAbort("Unexpected value found", key);
}
size_t sz = GenerateValue(value_base, value, sizeof(value));
if (value_from_db.length() != sz) {
VerificationAbort("Length of value read is not equal", key);
}
if (memcmp(value_from_db.data(), value, sz) != 0) {
VerificationAbort("Contents of value read don't match", key);
}
} else {
if (value_base != SharedState::SENTINEL) {
VerificationAbort("Value not found", key);
}
}
}
static void PrintKeyValue(uint32_t key, const char *value, size_t sz) {
if (!FLAGS_verbose) return;
fprintf(stdout, "%u ==> (%u) ", key, (unsigned int)sz);
for (size_t i=0; i<sz; i++) {
fprintf(stdout, "%X", value[i]);
}
fprintf(stdout, "\n");
}
static size_t GenerateValue(uint32_t rand, char *v, size_t max_sz) {
size_t value_sz = ((rand % 3) + 1) * FLAGS_value_size_mult;
assert(value_sz <= max_sz && value_sz >= sizeof(uint32_t));
*((uint32_t*)v) = rand;
for (size_t i=sizeof(uint32_t); i < value_sz; i++) {
v[i] = (char)(rand ^ i);
}
v[value_sz] = '\0';
return value_sz; // the size of the value set.
}
void PrintEnv() const {
fprintf(stdout, "LevelDB version : %d.%d\n",
kMajorVersion, kMinorVersion);
fprintf(stdout, "Number of threads : %d\n", FLAGS_threads);
fprintf(stdout,
"Ops per thread : %lu\n",
(unsigned long)FLAGS_ops_per_thread);
std::string ttl_state("unused");
if (FLAGS_ttl > 0) {
ttl_state = NumberToString(FLAGS_ttl);
}
fprintf(stdout, "Time to live(sec) : %s\n", ttl_state.c_str());
fprintf(stdout, "Read percentage : %d%%\n", FLAGS_readpercent);
fprintf(stdout, "Prefix percentage : %d%%\n", FLAGS_prefixpercent);
fprintf(stdout, "Write percentage : %d%%\n", FLAGS_writepercent);
fprintf(stdout, "Delete percentage : %d%%\n", FLAGS_delpercent);
fprintf(stdout, "Iterate percentage : %d%%\n", FLAGS_iterpercent);
fprintf(stdout, "Write-buffer-size : %d\n", FLAGS_write_buffer_size);
fprintf(stdout,
"Iterations : %lu\n",
(unsigned long)FLAGS_num_iterations);
fprintf(stdout,
"Max key : %lu\n",
(unsigned long)FLAGS_max_key);
fprintf(stdout, "Ratio #ops/#keys : %f\n",
(1.0 * FLAGS_ops_per_thread * FLAGS_threads)/FLAGS_max_key);
fprintf(stdout, "Num times DB reopens: %d\n", FLAGS_reopen);
fprintf(stdout, "Batches/snapshots : %d\n",
FLAGS_test_batches_snapshots);
fprintf(stdout, "Purge redundant %% : %d\n",
FLAGS_purge_redundant_percent);
fprintf(stdout, "Deletes use filter : %d\n",
FLAGS_filter_deletes);
fprintf(stdout, "Num keys per lock : %d\n",
1 << FLAGS_log2_keys_per_lock);
const char* compression = "";
switch (FLAGS_compression_type_e) {
case rocksdb::kNoCompression:
compression = "none";
break;
case rocksdb::kSnappyCompression:
compression = "snappy";
break;
case rocksdb::kZlibCompression:
compression = "zlib";
break;
case rocksdb::kBZip2Compression:
compression = "bzip2";
break;
}
fprintf(stdout, "Compression : %s\n", compression);
const char* memtablerep = "";
switch (FLAGS_rep_factory) {
case kSkipList:
memtablerep = "skip_list";
break;
case kHashSkipList:
memtablerep = "prefix_hash";
break;
case kVectorRep:
memtablerep = "vector";
break;
}
fprintf(stdout, "Memtablerep : %s\n", memtablerep);
fprintf(stdout, "------------------------------------------------\n");
}
void Open() {
assert(db_ == nullptr);
Options options;
options.block_cache = cache_;
options.block_cache_compressed = compressed_cache_;
options.write_buffer_size = FLAGS_write_buffer_size;
options.max_write_buffer_number = FLAGS_max_write_buffer_number;
options.min_write_buffer_number_to_merge =
FLAGS_min_write_buffer_number_to_merge;
options.max_background_compactions = FLAGS_max_background_compactions;
options.compaction_style =
static_cast<rocksdb::CompactionStyle>(FLAGS_compaction_style);
options.block_size = FLAGS_block_size;
options.filter_policy = filter_policy_;
options.prefix_extractor = prefix_extractor_;
options.max_open_files = FLAGS_open_files;
options.statistics = dbstats;
options.env = FLAGS_env;
options.disableDataSync = FLAGS_disable_data_sync;
options.use_fsync = FLAGS_use_fsync;
options.allow_mmap_reads = FLAGS_mmap_read;
rocksdb_kill_odds = FLAGS_kill_random_test;
options.target_file_size_base = FLAGS_target_file_size_base;
options.target_file_size_multiplier = FLAGS_target_file_size_multiplier;
options.max_bytes_for_level_base = FLAGS_max_bytes_for_level_base;
options.max_bytes_for_level_multiplier =
FLAGS_max_bytes_for_level_multiplier;
options.level0_stop_writes_trigger = FLAGS_level0_stop_writes_trigger;
options.level0_slowdown_writes_trigger =
FLAGS_level0_slowdown_writes_trigger;
options.level0_file_num_compaction_trigger =
FLAGS_level0_file_num_compaction_trigger;
options.compression = FLAGS_compression_type_e;
options.create_if_missing = true;
options.disable_seek_compaction = FLAGS_disable_seek_compaction;
options.delete_obsolete_files_period_micros =
FLAGS_delete_obsolete_files_period_micros;
options.max_manifest_file_size = 1024;
options.filter_deletes = FLAGS_filter_deletes;
if ((FLAGS_prefix_size == 0) == (FLAGS_rep_factory == kHashSkipList)) {
fprintf(stderr,
"prefix_size should be non-zero iff memtablerep == prefix_hash\n");
exit(1);
}
switch (FLAGS_rep_factory) {
case kHashSkipList:
options.memtable_factory.reset(NewHashSkipListRepFactory(
NewFixedPrefixTransform(FLAGS_prefix_size)));
break;
case kSkipList:
// no need to do anything
break;
case kVectorRep:
options.memtable_factory.reset(
new VectorRepFactory()
);
break;
}
static Random purge_percent(1000); // no benefit from non-determinism here
if (static_cast<int32_t>(purge_percent.Uniform(100)) <
FLAGS_purge_redundant_percent - 1) {
options.purge_redundant_kvs_while_flush = false;
}
if (FLAGS_use_merge) {
options.merge_operator = MergeOperators::CreatePutOperator();
}
// set universal style compaction configurations, if applicable
if (FLAGS_universal_size_ratio != 0) {
options.compaction_options_universal.size_ratio =
FLAGS_universal_size_ratio;
}
if (FLAGS_universal_min_merge_width != 0) {
options.compaction_options_universal.min_merge_width =
FLAGS_universal_min_merge_width;
}
if (FLAGS_universal_max_merge_width != 0) {
options.compaction_options_universal.max_merge_width =
FLAGS_universal_max_merge_width;
}
if (FLAGS_universal_max_size_amplification_percent != 0) {
options.compaction_options_universal.max_size_amplification_percent =
FLAGS_universal_max_size_amplification_percent;
}
fprintf(stdout, "DB path: [%s]\n", FLAGS_db.c_str());
Status s;
if (FLAGS_ttl == -1) {
s = DB::Open(options, FLAGS_db, &db_);
} else {
s = UtilityDB::OpenTtlDB(options, FLAGS_db, &sdb_, FLAGS_ttl);
db_ = sdb_;
}
if (!s.ok()) {
fprintf(stderr, "open error: %s\n", s.ToString().c_str());
exit(1);
}
}
void Reopen() {
// do not close the db. Just delete the lock file. This
// simulates a crash-recovery kind of situation.
if (FLAGS_ttl != -1) {
((DBWithTTL*) db_)->TEST_Destroy_DBWithTtl();
} else {
((DBImpl*) db_)->TEST_Destroy_DBImpl();
}
db_ = nullptr;
num_times_reopened_++;
double now = FLAGS_env->NowMicros();
fprintf(stdout, "%s Reopening database for the %dth time\n",
FLAGS_env->TimeToString((uint64_t) now/1000000).c_str(),
num_times_reopened_);
Open();
}
void PrintStatistics() {
if (dbstats) {
fprintf(stdout, "STATISTICS:\n%s\n", dbstats->ToString().c_str());
}
}
private:
shared_ptr<Cache> cache_;
shared_ptr<Cache> compressed_cache_;
const FilterPolicy* filter_policy_;
const SliceTransform* prefix_extractor_;
DB* db_;
StackableDB* sdb_;
int num_times_reopened_;
};
} // namespace rocksdb
int main(int argc, char** argv) {
google::SetUsageMessage(std::string("\nUSAGE:\n") + std::string(argv[0]) +
" [OPTIONS]...");
google::ParseCommandLineFlags(&argc, &argv, true);
if (FLAGS_statistics) {
dbstats = rocksdb::CreateDBStatistics();
}
FLAGS_compression_type_e =
StringToCompressionType(FLAGS_compression_type.c_str());
if (!FLAGS_hdfs.empty()) {
FLAGS_env = new rocksdb::HdfsEnv(FLAGS_hdfs);
}
FLAGS_rep_factory = StringToRepFactory(FLAGS_memtablerep.c_str());
// The number of background threads should be at least as much the
// max number of concurrent compactions.
FLAGS_env->SetBackgroundThreads(FLAGS_max_background_compactions);
if ((FLAGS_readpercent + FLAGS_prefixpercent +
FLAGS_writepercent + FLAGS_delpercent + FLAGS_iterpercent) != 100) {
fprintf(stderr,
"Error: Read+Prefix+Write+Delete+Iterate percents != 100!\n");
exit(1);
}
if (FLAGS_disable_wal == 1 && FLAGS_reopen > 0) {
fprintf(stderr, "Error: Db cannot reopen safely with disable_wal set!\n");
exit(1);
}
if ((unsigned)FLAGS_reopen >= FLAGS_ops_per_thread) {
fprintf(stderr,
"Error: #DB-reopens should be < ops_per_thread\n"
"Provided reopens = %d and ops_per_thread = %lu\n",
FLAGS_reopen,
(unsigned long)FLAGS_ops_per_thread);
exit(1);
}
// Choose a location for the test database if none given with --db=<path>
if (FLAGS_db.empty()) {
std::string default_db_path;
rocksdb::Env::Default()->GetTestDirectory(&default_db_path);
default_db_path += "/dbstress";
FLAGS_db = default_db_path;
}
rocksdb::StressTest stress;
stress.Run();
return 0;
}