rocksdb/db_stress_tool/db_stress_tool.cc
Andrew Kryczka 03c4ea26bb db_stress option to preserve all files until verification success (#10659)
Summary:
In `db_stress`, DB and expected state files containing changes leading up to a verification failure are often deleted, which makes debugging such failures difficult. On the DB side, flushed WAL files and compacted SST files are marked obsolete and then deleted. Without those files, we cannot pinpoint where a key that failed verification changed unexpectedly. On the expected state side, files for verifying prefix-recoverability in the presence of unsynced data loss are deleted before verification. These include a baseline state file containing the expected state at the time of the last successful verification, and a trace file containing all operations since then. Without those files, we cannot know the sequence of DB operations expected to be recovered.

This PR attempts to address this gap with a new `db_stress` flag: `preserve_unverified_changes`. Setting `preserve_unverified_changes=1` has two effects.

First, prior to startup verification, `db_stress` hardlinks all DB and expected state files in "unverified/" subdirectories of `FLAGS_db` and `FLAGS_expected_values_dir`. The separate directories are needed because the pre-verification opening process deletes files written by the previous `db_stress` run as described above. These "unverified/" subdirectories are cleaned up following startup verification success.

I considered other approaches for preserving DB files through startup verification, like using a read-only DB or preventing deletion of DB files externally, e.g., in the `Env` layer. However, I decided against it since such an approach would not work for expected state files, and I did not want to change the DB management logic. If there were a way to disable DB file deletions before regular DB open, I would have preferred to use that.

Second, `db_stress` attempts to keep all DB and expected state files that were live at some point since the start of the `db_stress` run. This is a bit tricky and involves the following changes.

- Open the DB with `disable_auto_compactions=1` and `avoid_flush_during_recovery=1`
- DisableFileDeletions()
- EnableAutoCompactions()

For this part, too, I would have preferred to use a hypothetical API that disables DB file deletion before regular DB open.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10659

Reviewed By: hx235

Differential Revision: D39407454

Pulled By: ajkr

fbshipit-source-id: 6e981025c7dce147649d2e770728471395a7fa53
2022-09-12 14:49:38 -07:00

348 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.
//
// 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.
#ifdef GFLAGS
#include "db_stress_tool/db_stress_common.h"
#include "db_stress_tool/db_stress_driver.h"
#include "rocksdb/convenience.h"
#include "utilities/fault_injection_fs.h"
namespace ROCKSDB_NAMESPACE {
namespace {
static std::shared_ptr<ROCKSDB_NAMESPACE::Env> env_guard;
static std::shared_ptr<ROCKSDB_NAMESPACE::DbStressEnvWrapper> env_wrapper_guard;
static std::shared_ptr<ROCKSDB_NAMESPACE::DbStressEnvWrapper>
dbsl_env_wrapper_guard;
static std::shared_ptr<CompositeEnvWrapper> fault_env_guard;
} // namespace
KeyGenContext key_gen_ctx;
int db_stress_tool(int argc, char** argv) {
SetUsageMessage(std::string("\nUSAGE:\n") + std::string(argv[0]) +
" [OPTIONS]...");
ParseCommandLineFlags(&argc, &argv, true);
SanitizeDoubleParam(&FLAGS_bloom_bits);
SanitizeDoubleParam(&FLAGS_memtable_prefix_bloom_size_ratio);
SanitizeDoubleParam(&FLAGS_max_bytes_for_level_multiplier);
#ifndef NDEBUG
if (FLAGS_mock_direct_io) {
SetupSyncPointsToMockDirectIO();
}
#endif
if (FLAGS_statistics) {
dbstats = ROCKSDB_NAMESPACE::CreateDBStatistics();
if (FLAGS_test_secondary) {
dbstats_secondaries = ROCKSDB_NAMESPACE::CreateDBStatistics();
}
}
compression_type_e = StringToCompressionType(FLAGS_compression_type.c_str());
bottommost_compression_type_e =
StringToCompressionType(FLAGS_bottommost_compression_type.c_str());
checksum_type_e = StringToChecksumType(FLAGS_checksum_type.c_str());
Env* raw_env;
int env_opts = !FLAGS_env_uri.empty() + !FLAGS_fs_uri.empty();
if (env_opts > 1) {
fprintf(stderr, "Error: --env_uri and --fs_uri are mutually exclusive\n");
exit(1);
}
Status s = Env::CreateFromUri(ConfigOptions(), FLAGS_env_uri, FLAGS_fs_uri,
&raw_env, &env_guard);
if (!s.ok()) {
fprintf(stderr, "Error Creating Env URI: %s: %s\n", FLAGS_env_uri.c_str(),
s.ToString().c_str());
exit(1);
}
dbsl_env_wrapper_guard = std::make_shared<DbStressEnvWrapper>(raw_env);
db_stress_listener_env = dbsl_env_wrapper_guard.get();
if (FLAGS_read_fault_one_in || FLAGS_sync_fault_injection ||
FLAGS_write_fault_one_in || FLAGS_open_metadata_write_fault_one_in ||
FLAGS_open_write_fault_one_in || FLAGS_open_read_fault_one_in) {
FaultInjectionTestFS* fs =
new FaultInjectionTestFS(raw_env->GetFileSystem());
fault_fs_guard.reset(fs);
if (FLAGS_write_fault_one_in) {
fault_fs_guard->SetFilesystemDirectWritable(false);
} else {
fault_fs_guard->SetFilesystemDirectWritable(true);
}
fault_env_guard =
std::make_shared<CompositeEnvWrapper>(raw_env, fault_fs_guard);
raw_env = fault_env_guard.get();
}
env_wrapper_guard = std::make_shared<DbStressEnvWrapper>(raw_env);
db_stress_env = env_wrapper_guard.get();
if (FLAGS_write_fault_one_in) {
// In the write injection case, we need to use the FS interface and returns
// the IOStatus with different error and flags. Therefore,
// DbStressEnvWrapper cannot be used which will swallow the FS
// implementations. We should directly use the raw_env which is the
// CompositeEnvWrapper of env and fault_fs.
db_stress_env = raw_env;
}
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.
db_stress_env->SetBackgroundThreads(FLAGS_max_background_compactions,
ROCKSDB_NAMESPACE::Env::Priority::LOW);
db_stress_env->SetBackgroundThreads(FLAGS_num_bottom_pri_threads,
ROCKSDB_NAMESPACE::Env::Priority::BOTTOM);
if (FLAGS_prefixpercent > 0 && FLAGS_prefix_size < 0) {
fprintf(stderr,
"Error: prefixpercent is non-zero while prefix_size is "
"not positive!\n");
exit(1);
}
if (FLAGS_test_batches_snapshots && FLAGS_prefix_size <= 0) {
fprintf(stderr,
"Error: please specify prefix_size for "
"test_batches_snapshots test!\n");
exit(1);
}
if (FLAGS_memtable_prefix_bloom_size_ratio > 0.0 && FLAGS_prefix_size < 0 &&
!FLAGS_memtable_whole_key_filtering) {
fprintf(stderr,
"Error: please specify positive prefix_size or enable whole key "
"filtering in order to use memtable_prefix_bloom_size_ratio\n");
exit(1);
}
if ((FLAGS_readpercent + FLAGS_prefixpercent + FLAGS_writepercent +
FLAGS_delpercent + FLAGS_delrangepercent + FLAGS_iterpercent +
FLAGS_customopspercent) != 100) {
fprintf(
stderr,
"Error: "
"Read(-readpercent=%d)+Prefix(-prefixpercent=%d)+Write(-writepercent=%"
"d)+Delete(-delpercent=%d)+DeleteRange(-delrangepercent=%d)"
"+Iterate(-iterpercent=%d)+CustomOps(-customopspercent=%d) percents != "
"100!\n",
FLAGS_readpercent, FLAGS_prefixpercent, FLAGS_writepercent,
FLAGS_delpercent, FLAGS_delrangepercent, FLAGS_iterpercent,
FLAGS_customopspercent);
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);
}
if (FLAGS_test_batches_snapshots && FLAGS_delrangepercent > 0) {
fprintf(stderr,
"Error: nonzero delrangepercent unsupported in "
"test_batches_snapshots mode\n");
exit(1);
}
if (FLAGS_active_width > FLAGS_max_key) {
fprintf(stderr, "Error: active_width can be at most max_key\n");
exit(1);
} else if (FLAGS_active_width == 0) {
FLAGS_active_width = FLAGS_max_key;
}
if (FLAGS_value_size_mult * kRandomValueMaxFactor > kValueMaxLen) {
fprintf(stderr, "Error: value_size_mult can be at most %d\n",
kValueMaxLen / kRandomValueMaxFactor);
exit(1);
}
if (FLAGS_use_merge && FLAGS_nooverwritepercent == 100) {
fprintf(
stderr,
"Error: nooverwritepercent must not be 100 when using merge operands");
exit(1);
}
if (FLAGS_ingest_external_file_one_in > 0 &&
FLAGS_nooverwritepercent == 100) {
fprintf(
stderr,
"Error: nooverwritepercent must not be 100 when using file ingestion");
exit(1);
}
if (FLAGS_clear_column_family_one_in > 0 && FLAGS_backup_one_in > 0) {
fprintf(stderr,
"Error: clear_column_family_one_in must be 0 when using backup\n");
exit(1);
}
if (FLAGS_test_cf_consistency && FLAGS_disable_wal) {
FLAGS_atomic_flush = true;
}
if (FLAGS_read_only) {
if (FLAGS_writepercent != 0 || FLAGS_delpercent != 0 ||
FLAGS_delrangepercent != 0) {
fprintf(stderr, "Error: updates are not supported in read only mode\n");
exit(1);
} else if (FLAGS_checkpoint_one_in > 0 &&
FLAGS_clear_column_family_one_in > 0) {
fprintf(stdout,
"Warn: checkpoint won't be validated since column families may "
"be dropped.\n");
}
}
// Choose a location for the test database if none given with --db=<path>
if (FLAGS_db.empty()) {
std::string default_db_path;
db_stress_env->GetTestDirectory(&default_db_path);
default_db_path += "/dbstress";
FLAGS_db = default_db_path;
}
if ((FLAGS_test_secondary || FLAGS_continuous_verification_interval > 0) &&
FLAGS_secondaries_base.empty()) {
std::string default_secondaries_path;
db_stress_env->GetTestDirectory(&default_secondaries_path);
default_secondaries_path += "/dbstress_secondaries";
s = db_stress_env->CreateDirIfMissing(default_secondaries_path);
if (!s.ok()) {
fprintf(stderr, "Failed to create directory %s: %s\n",
default_secondaries_path.c_str(), s.ToString().c_str());
exit(1);
}
FLAGS_secondaries_base = default_secondaries_path;
}
if (FLAGS_best_efforts_recovery && !FLAGS_skip_verifydb &&
!FLAGS_disable_wal) {
fprintf(stderr,
"With best-efforts recovery, either skip_verifydb or disable_wal "
"should be set to true.\n");
exit(1);
}
if (FLAGS_skip_verifydb) {
if (FLAGS_verify_db_one_in > 0) {
fprintf(stderr,
"Must set -verify_db_one_in=0 if skip_verifydb is true.\n");
exit(1);
}
if (FLAGS_continuous_verification_interval > 0) {
fprintf(stderr,
"Must set -continuous_verification_interval=0 if skip_verifydb "
"is true.\n");
exit(1);
}
}
if (FLAGS_enable_compaction_filter &&
(FLAGS_acquire_snapshot_one_in > 0 || FLAGS_compact_range_one_in > 0 ||
FLAGS_iterpercent > 0 || FLAGS_test_batches_snapshots ||
FLAGS_test_cf_consistency)) {
fprintf(
stderr,
"Error: acquire_snapshot_one_in, compact_range_one_in, iterpercent, "
"test_batches_snapshots must all be 0 when using compaction filter\n");
exit(1);
}
if (FLAGS_test_multi_ops_txns) {
CheckAndSetOptionsForMultiOpsTxnStressTest();
}
if (FLAGS_create_timestamped_snapshot_one_in > 0) {
if (!FLAGS_use_txn) {
fprintf(stderr, "timestamped snapshot supported only in TransactionDB\n");
exit(1);
} else if (FLAGS_txn_write_policy != 0) {
fprintf(stderr,
"timestamped snapshot supported only in write-committed\n");
exit(1);
}
}
if (FLAGS_preserve_unverified_changes && FLAGS_reopen != 0) {
fprintf(stderr,
"Reopen DB is incompatible with preserving unverified changes\n");
exit(1);
}
#ifndef NDEBUG
KillPoint* kp = KillPoint::GetInstance();
kp->rocksdb_kill_odds = FLAGS_kill_random_test;
kp->rocksdb_kill_exclude_prefixes = SplitString(FLAGS_kill_exclude_prefixes);
#endif
unsigned int levels = FLAGS_max_key_len;
std::vector<std::string> weights;
uint64_t scale_factor = FLAGS_key_window_scale_factor;
key_gen_ctx.window = scale_factor * 100;
if (!FLAGS_key_len_percent_dist.empty()) {
weights = SplitString(FLAGS_key_len_percent_dist);
if (weights.size() != levels) {
fprintf(stderr,
"Number of weights in key_len_dist should be equal to"
" max_key_len");
exit(1);
}
uint64_t total_weight = 0;
for (std::string& weight : weights) {
uint64_t val = std::stoull(weight);
key_gen_ctx.weights.emplace_back(val * scale_factor);
total_weight += val;
}
if (total_weight != 100) {
fprintf(stderr, "Sum of all weights in key_len_dist should be 100");
exit(1);
}
} else {
uint64_t keys_per_level = key_gen_ctx.window / levels;
for (unsigned int level = 0; level + 1 < levels; ++level) {
key_gen_ctx.weights.emplace_back(keys_per_level);
}
key_gen_ctx.weights.emplace_back(key_gen_ctx.window -
keys_per_level * (levels - 1));
}
std::unique_ptr<ROCKSDB_NAMESPACE::StressTest> stress;
if (FLAGS_test_cf_consistency) {
stress.reset(CreateCfConsistencyStressTest());
} else if (FLAGS_test_batches_snapshots) {
stress.reset(CreateBatchedOpsStressTest());
} else if (FLAGS_test_multi_ops_txns) {
stress.reset(CreateMultiOpsTxnsStressTest());
} else {
stress.reset(CreateNonBatchedOpsStressTest());
}
// Initialize the Zipfian pre-calculated array
InitializeHotKeyGenerator(FLAGS_hot_key_alpha);
if (RunStressTest(stress.get())) {
return 0;
} else {
return 1;
}
}
} // namespace ROCKSDB_NAMESPACE
#endif // GFLAGS