rocksdb/db_stress_tool/db_stress_gflags.cc
Yanqin Jin 1777e5f7e9 Snapshots with user-specified timestamps (#9879)
Summary:
In RocksDB, keys are associated with (internal) sequence numbers which denote when the keys are written
to the database. Sequence numbers in different RocksDB instances are unrelated, thus not comparable.

It is nice if we can associate sequence numbers with their corresponding actual timestamps. One thing we can
do is to support user-defined timestamp, which allows the applications to specify the format of custom timestamps
and encode a timestamp with each key. More details can be found at https://github.com/facebook/rocksdb/wiki/User-defined-Timestamp-%28Experimental%29.

This PR provides a different but complementary approach. We can associate rocksdb snapshots (defined in
https://github.com/facebook/rocksdb/blob/7.2.fb/include/rocksdb/snapshot.h#L20) with **user-specified** timestamps.
Since a snapshot is essentially an object representing a sequence number, this PR establishes a bi-directional mapping between sequence numbers and timestamps.

In the past, snapshots are usually taken by readers. The current super-version is grabbed, and a `rocksdb::Snapshot`
object is created with the last published sequence number of the super-version. You can see that the reader actually
has no good idea of what timestamp to assign to this snapshot, because by the time the `GetSnapshot()` is called,
an arbitrarily long period of time may have already elapsed since the last write, which is when the last published
sequence number is written.

This observation motivates the creation of "timestamped" snapshots on the write path. Currently, this functionality is
exposed only to the layer of `TransactionDB`. Application can tell RocksDB to create a snapshot when a transaction
commits, effectively associating the last sequence number with a timestamp. It is also assumed that application will
ensure any two snapshots with timestamps should satisfy the following:
```
snapshot1.seq < snapshot2.seq iff. snapshot1.ts < snapshot2.ts
```

If the application can guarantee that when a reader takes a timestamped snapshot, there is no active writes going on
in the database, then we also allow the user to use a new API `TransactionDB::CreateTimestampedSnapshot()` to create
a snapshot with associated timestamp.

Code example
```cpp
// Create a timestamped snapshot when committing transaction.
txn->SetCommitTimestamp(100);
txn->SetSnapshotOnNextOperation();
txn->Commit();

// A wrapper API for convenience
Status Transaction::CommitAndTryCreateSnapshot(
    std::shared_ptr<TransactionNotifier> notifier,
    TxnTimestamp ts,
    std::shared_ptr<const Snapshot>* ret);

// Create a timestamped snapshot if caller guarantees no concurrent writes
std::pair<Status, std::shared_ptr<const Snapshot>> snapshot = txn_db->CreateTimestampedSnapshot(100);
```

The snapshots created in this way will be managed by RocksDB with ref-counting and potentially shared with
other readers. We provide the following APIs for readers to retrieve a snapshot given a timestamp.
```cpp
// Return the timestamped snapshot correponding to given timestamp. If ts is
// kMaxTxnTimestamp, then we return the latest timestamped snapshot if present.
// Othersise, we return the snapshot whose timestamp is equal to `ts`. If no
// such snapshot exists, then we return null.
std::shared_ptr<const Snapshot> TransactionDB::GetTimestampedSnapshot(TxnTimestamp ts) const;
// Return the latest timestamped snapshot if present.
std::shared_ptr<const Snapshot> TransactionDB::GetLatestTimestampedSnapshot() const;
```

We also provide two additional APIs for stats collection and reporting purposes.

```cpp
Status TransactionDB::GetAllTimestampedSnapshots(
    std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
// Return timestamped snapshots whose timestamps fall in [ts_lb, ts_ub) and store them in `snapshots`.
Status TransactionDB::GetTimestampedSnapshots(
    TxnTimestamp ts_lb,
    TxnTimestamp ts_ub,
    std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
```

To prevent the number of timestamped snapshots from growing infinitely, we provide the following API to release
timestamped snapshots whose timestamps are older than or equal to a given threshold.
```cpp
void TransactionDB::ReleaseTimestampedSnapshotsOlderThan(TxnTimestamp ts);
```

Before shutdown, RocksDB will release all timestamped snapshots.

Comparison with user-defined timestamp and how they can be combined:
User-defined timestamp persists every key with a timestamp, while timestamped snapshots maintain a volatile
mapping between snapshots (sequence numbers) and timestamps.
Different internal keys with the same user key but different timestamps will be treated as different by compaction,
thus a newer version will not hide older versions (with smaller timestamps) unless they are eligible for garbage collection.
In contrast, taking a timestamped snapshot at a certain sequence number and timestamp prevents all the keys visible in
this snapshot from been dropped by compaction. Here, visible means (seq < snapshot and most recent).
The timestamped snapshot supports the semantics of reading at an exact point in time.

Timestamped snapshots can also be used with user-defined timestamp.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9879

Test Plan:
```
make check
TEST_TMPDIR=/dev/shm make crash_test_with_txn
```

Reviewed By: siying

Differential Revision: D35783919

Pulled By: riversand963

fbshipit-source-id: 586ad905e169189e19d3bfc0cb0177a7239d1bd4
2022-06-10 16:07:03 -07:00

975 lines
41 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.
#ifdef GFLAGS
#include "db_stress_tool/db_stress_common.h"
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. When --nooverwritepercent is "
"nonzero and --expected_values_dir is nonempty, this value "
"must be fixed across invocations.");
static const bool FLAGS_seed_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_seed, &ValidateUint32Range);
DEFINE_bool(read_only, false, "True if open DB in read-only mode during tests");
DEFINE_int64(max_key, 1 * KB * KB,
"Max number of key/values to place in database");
DEFINE_int32(max_key_len, 3, "Maximum length of a key in 8-byte units");
DEFINE_string(key_len_percent_dist, "",
"Percentages of keys of various lengths. For example, 1,30,69 "
"means 1% of keys are 8 bytes, 30% are 16 bytes, and 69% are "
"24 bytes. If not specified, it will be evenly distributed");
DEFINE_int32(key_window_scale_factor, 10,
"This value will be multiplied by 100 to come up with a window "
"size for varying the key length");
DEFINE_int32(column_families, 10, "Number of column families");
DEFINE_double(
hot_key_alpha, 0,
"Use Zipfian distribution to generate the key "
"distribution. If it is not specified, write path will use random "
"distribution to generate the keys. The parameter is [0, double_max]). "
"However, the larger alpha is, the more shewed will be. If alpha is "
"larger than 2, it is likely that only 1 key will be accessed. The "
"Recommended value is [0.8-1.5]. The distribution is also related to "
"max_key and total iterations of generating the hot key. ");
DEFINE_string(
options_file, "",
"The path to a RocksDB options file. If specified, then db_stress will "
"run with the RocksDB options in the default column family of the "
"specified options file. Note that, when an options file is provided, "
"db_stress will ignore the flag values for all options that may be passed "
"via options file.");
DEFINE_int64(
active_width, 0,
"Number of keys in active span of the key-range at any given time. The "
"span begins with its left endpoint at key 0, gradually moves rightwards, "
"and ends with its right endpoint at max_key. If set to 0, active_width "
"will be sanitized to be equal to max_key.");
// TODO(noetzli) Add support for single deletes
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_bool(atomic_flush, false,
"If set, enables atomic flush in the options.\n");
DEFINE_bool(test_cf_consistency, false,
"If set, runs the stress test dedicated to verifying writes to "
"multiple column families are consistent. Setting this implies "
"`atomic_flush=true` is set true if `disable_wal=false`.\n");
DEFINE_bool(test_multi_ops_txns, false,
"If set, runs stress test dedicated to verifying multi-ops "
"transactions on a simple relational table with primary and "
"secondary index.");
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_int32(compaction_readahead_size, 0, "Compaction readahead size");
DEFINE_bool(enable_pipelined_write, false, "Pipeline WAL/memtable writes");
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_bool(progress_reports, true,
"If true, db_stress will report number of finished operations");
DEFINE_uint64(db_write_buffer_size,
ROCKSDB_NAMESPACE::Options().db_write_buffer_size,
"Number of bytes to buffer in all memtables before compacting");
DEFINE_int32(
write_buffer_size,
static_cast<int32_t>(ROCKSDB_NAMESPACE::Options().write_buffer_size),
"Number of bytes to buffer in memtable before compacting");
DEFINE_int32(max_write_buffer_number,
ROCKSDB_NAMESPACE::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_NAMESPACE::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(max_write_buffer_number_to_maintain,
ROCKSDB_NAMESPACE::Options().max_write_buffer_number_to_maintain,
"The total maximum number of write buffers to maintain in memory "
"including copies of buffers that have already been flushed. "
"Unlike max_write_buffer_number, this parameter does not affect "
"flushing. This controls the minimum amount of write history "
"that will be available in memory for conflict checking when "
"Transactions are used. If this value is too low, some "
"transactions may fail at commit time due to not being able to "
"determine whether there were any write conflicts. Setting this "
"value to 0 will cause write buffers to be freed immediately "
"after they are flushed. If this value is set to -1, "
"'max_write_buffer_number' will be used.");
DEFINE_int64(max_write_buffer_size_to_maintain,
ROCKSDB_NAMESPACE::Options().max_write_buffer_size_to_maintain,
"The total maximum size of write buffers to maintain in memory "
"including copies of buffers that have already been flushed. "
"Unlike max_write_buffer_number, this parameter does not affect "
"flushing. This controls the minimum amount of write history "
"that will be available in memory for conflict checking when "
"Transactions are used. If this value is too low, some "
"transactions may fail at commit time due to not being able to "
"determine whether there were any write conflicts. Setting this "
"value to 0 will cause write buffers to be freed immediately "
"after they are flushed. If this value is set to -1, "
"'max_write_buffer_number' will be used.");
DEFINE_double(memtable_prefix_bloom_size_ratio,
ROCKSDB_NAMESPACE::Options().memtable_prefix_bloom_size_ratio,
"creates prefix blooms for memtables, each with size "
"`write_buffer_size * memtable_prefix_bloom_size_ratio`.");
DEFINE_bool(memtable_whole_key_filtering,
ROCKSDB_NAMESPACE::Options().memtable_whole_key_filtering,
"Enable whole key filtering in memtables.");
DEFINE_int32(open_files, ROCKSDB_NAMESPACE::Options().max_open_files,
"Maximum number of files to keep open at the same time "
"(use default if == 0)");
DEFINE_int64(compressed_cache_size, 0,
"Number of bytes to use as a cache of compressed data."
" 0 means use default settings.");
DEFINE_int32(
compressed_cache_numshardbits, -1,
"Number of shards for the compressed block cache is 2 ** "
"compressed_cache_numshardbits. Negative value means default settings. "
"This is applied only if compressed_cache_size is greater than 0.");
DEFINE_int32(compaction_style, ROCKSDB_NAMESPACE::Options().compaction_style,
"");
DEFINE_int32(num_levels, ROCKSDB_NAMESPACE::Options().num_levels,
"Number of levels in the DB");
DEFINE_int32(level0_file_num_compaction_trigger,
ROCKSDB_NAMESPACE::Options().level0_file_num_compaction_trigger,
"Level0 compaction start trigger");
DEFINE_int32(level0_slowdown_writes_trigger,
ROCKSDB_NAMESPACE::Options().level0_slowdown_writes_trigger,
"Number of files in level-0 that will slow down writes");
DEFINE_int32(level0_stop_writes_trigger,
ROCKSDB_NAMESPACE::Options().level0_stop_writes_trigger,
"Number of files in level-0 that will trigger put stop.");
DEFINE_int32(block_size,
static_cast<int32_t>(
ROCKSDB_NAMESPACE::BlockBasedTableOptions().block_size),
"Number of bytes in a block.");
DEFINE_int32(format_version,
static_cast<int32_t>(
ROCKSDB_NAMESPACE::BlockBasedTableOptions().format_version),
"Format version of SST files.");
DEFINE_int32(
index_block_restart_interval,
ROCKSDB_NAMESPACE::BlockBasedTableOptions().index_block_restart_interval,
"Number of keys between restart points "
"for delta encoding of keys in index block.");
DEFINE_bool(disable_auto_compactions,
ROCKSDB_NAMESPACE::Options().disable_auto_compactions,
"If true, RocksDB internally will not trigger compactions.");
DEFINE_int32(max_background_compactions,
ROCKSDB_NAMESPACE::Options().max_background_compactions,
"The maximum number of concurrent background compactions "
"that can occur in parallel.");
DEFINE_int32(num_bottom_pri_threads, 0,
"The number of threads in the bottom-priority thread pool (used "
"by universal compaction only).");
DEFINE_int32(compaction_thread_pool_adjust_interval, 0,
"The interval (in milliseconds) to adjust compaction thread pool "
"size. Don't change it periodically if the value is 0.");
DEFINE_int32(compaction_thread_pool_variations, 2,
"Range of background thread pool size variations when adjusted "
"periodically.");
DEFINE_int32(max_background_flushes,
ROCKSDB_NAMESPACE::Options().max_background_flushes,
"The maximum number of concurrent background flushes "
"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_int32(clear_column_family_one_in, 1000000,
"With a chance of 1/N, delete a column family and then recreate "
"it again. If N == 0, never drop/create column families. "
"When test_batches_snapshots is true, this flag has no effect");
DEFINE_int32(get_live_files_one_in, 1000000,
"With a chance of 1/N, call GetLiveFiles to verify if it returns "
"correctly. If N == 0, do not call the interface.");
DEFINE_int32(
get_sorted_wal_files_one_in, 1000000,
"With a chance of 1/N, call GetSortedWalFiles to verify if it returns "
"correctly. (Note that this API may legitimately return an error.) If N == "
"0, do not call the interface.");
DEFINE_int32(
get_current_wal_file_one_in, 1000000,
"With a chance of 1/N, call GetCurrentWalFile to verify if it returns "
"correctly. (Note that this API may legitimately return an error.) If N == "
"0, do not call the interface.");
DEFINE_int32(set_options_one_in, 0,
"With a chance of 1/N, change some random options");
DEFINE_int32(set_in_place_one_in, 0,
"With a chance of 1/N, toggle in place support option");
DEFINE_int64(cache_size, 2LL * KB * KB * KB,
"Number of bytes to use as a cache of uncompressed data.");
DEFINE_int32(cache_numshardbits, 6,
"Number of shards for the block cache"
" is 2 ** cache_numshardbits. Negative means use default settings."
" This is applied only if FLAGS_cache_size is non-negative.");
DEFINE_bool(cache_index_and_filter_blocks, false,
"True if indexes/filters should be cached in block cache.");
DEFINE_bool(charge_compression_dictionary_building_buffer, false,
"Setting for "
"CacheEntryRoleOptions::charged of"
"CacheEntryRole::kCompressionDictionaryBuildingBuffer");
DEFINE_bool(charge_filter_construction, false,
"Setting for "
"CacheEntryRoleOptions::charged of"
"CacheEntryRole::kFilterConstruction");
DEFINE_bool(charge_table_reader, false,
"Setting for "
"CacheEntryRoleOptions::charged of"
"CacheEntryRole::kBlockBasedTableReader");
DEFINE_int32(
top_level_index_pinning,
static_cast<int32_t>(ROCKSDB_NAMESPACE::PinningTier::kFallback),
"Type of pinning for top-level indexes into metadata partitions (see "
"`enum PinningTier` in table.h)");
DEFINE_int32(
partition_pinning,
static_cast<int32_t>(ROCKSDB_NAMESPACE::PinningTier::kFallback),
"Type of pinning for metadata partitions (see `enum PinningTier` in "
"table.h)");
DEFINE_int32(
unpartitioned_pinning,
static_cast<int32_t>(ROCKSDB_NAMESPACE::PinningTier::kFallback),
"Type of pinning for unpartitioned metadata blocks (see `enum PinningTier` "
"in table.h)");
DEFINE_string(cache_type, "lru_cache", "Type of block cache.");
DEFINE_uint64(subcompactions, 1,
"Maximum number of subcompactions to divide L0-L1 compactions "
"into.");
DEFINE_uint64(periodic_compaction_seconds, 1000,
"Files older than this value will be picked up for compaction.");
DEFINE_uint64(compaction_ttl, 1000,
"Files older than TTL will be compacted to the next level.");
DEFINE_bool(allow_concurrent_memtable_write, false,
"Allow multi-writers to update mem tables in parallel.");
DEFINE_double(experimental_mempurge_threshold, 0.0,
"Maximum estimated useful payload that triggers a "
"mempurge process to collect memtable garbage bytes.");
DEFINE_bool(enable_write_thread_adaptive_yield, true,
"Use a yielding spin loop for brief writer thread waits.");
#ifndef ROCKSDB_LITE
// Options for StackableDB-based BlobDB
DEFINE_bool(use_blob_db, false, "[Stacked BlobDB] Use BlobDB.");
DEFINE_uint64(
blob_db_min_blob_size,
ROCKSDB_NAMESPACE::blob_db::BlobDBOptions().min_blob_size,
"[Stacked BlobDB] Smallest blob to store in a file. Blobs "
"smaller than this will be inlined with the key in the LSM tree.");
DEFINE_uint64(
blob_db_bytes_per_sync,
ROCKSDB_NAMESPACE::blob_db::BlobDBOptions().bytes_per_sync,
"[Stacked BlobDB] Sync blob files once per every N bytes written.");
DEFINE_uint64(blob_db_file_size,
ROCKSDB_NAMESPACE::blob_db::BlobDBOptions().blob_file_size,
"[Stacked BlobDB] Target size of each blob file.");
DEFINE_bool(
blob_db_enable_gc,
ROCKSDB_NAMESPACE::blob_db::BlobDBOptions().enable_garbage_collection,
"[Stacked BlobDB] Enable BlobDB garbage collection.");
DEFINE_double(
blob_db_gc_cutoff,
ROCKSDB_NAMESPACE::blob_db::BlobDBOptions().garbage_collection_cutoff,
"[Stacked BlobDB] Cutoff ratio for BlobDB garbage collection.");
#endif // !ROCKSDB_LITE
// Options for integrated BlobDB
DEFINE_bool(allow_setting_blob_options_dynamically, false,
"[Integrated BlobDB] Allow setting blob options dynamically.");
DEFINE_bool(
enable_blob_files,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions().enable_blob_files,
"[Integrated BlobDB] Enable writing large values to separate blob files.");
DEFINE_uint64(min_blob_size,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions().min_blob_size,
"[Integrated BlobDB] The size of the smallest value to be stored "
"separately in a blob file.");
DEFINE_uint64(blob_file_size,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions().blob_file_size,
"[Integrated BlobDB] The size limit for blob files.");
DEFINE_string(blob_compression_type, "none",
"[Integrated BlobDB] The compression algorithm to use for large "
"values stored in blob files.");
DEFINE_bool(enable_blob_garbage_collection,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions()
.enable_blob_garbage_collection,
"[Integrated BlobDB] Enable blob garbage collection.");
DEFINE_double(blob_garbage_collection_age_cutoff,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions()
.blob_garbage_collection_age_cutoff,
"[Integrated BlobDB] The cutoff in terms of blob file age for "
"garbage collection.");
DEFINE_double(blob_garbage_collection_force_threshold,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions()
.blob_garbage_collection_force_threshold,
"[Integrated BlobDB] The threshold for the ratio of garbage in "
"the oldest blob files for forcing garbage collection.");
DEFINE_uint64(blob_compaction_readahead_size,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions()
.blob_compaction_readahead_size,
"[Integrated BlobDB] Compaction readahead for blob files.");
DEFINE_int32(
blob_file_starting_level,
ROCKSDB_NAMESPACE::AdvancedColumnFamilyOptions().blob_file_starting_level,
"[Integrated BlobDB] Enable writing blob files during flushes and "
"compactions starting from the specified level.");
static const bool FLAGS_subcompactions_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_subcompactions, &ValidateUint32Range);
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 __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_reopen, &ValidateInt32Positive);
DEFINE_double(bloom_bits, 10,
"Bloom filter bits per key. "
"Negative means use default settings.");
DEFINE_bool(use_block_based_filter, false,
"use block based filter"
"instead of full filter for block based table");
DEFINE_int32(
ribbon_starting_level, 999,
"Use Bloom filter on levels below specified and Ribbon beginning on level "
"specified. Flush is considered level -1. 999 or more -> always Bloom. 0 "
"-> Ribbon except Bloom for flush. -1 -> always Ribbon.");
DEFINE_bool(partition_filters, false,
"use partitioned filters "
"for block-based table");
DEFINE_bool(
optimize_filters_for_memory,
ROCKSDB_NAMESPACE::BlockBasedTableOptions().optimize_filters_for_memory,
"Minimize memory footprint of filters");
DEFINE_bool(
detect_filter_construct_corruption,
ROCKSDB_NAMESPACE::BlockBasedTableOptions()
.detect_filter_construct_corruption,
"Detect corruption during new Bloom Filter and Ribbon Filter construction");
DEFINE_int32(
index_type,
static_cast<int32_t>(
ROCKSDB_NAMESPACE::BlockBasedTableOptions::kBinarySearch),
"Type of block-based table index (see `enum IndexType` in table.h)");
DEFINE_string(db, "", "Use the db with the following name.");
DEFINE_string(secondaries_base, "",
"Use this path as the base path for secondary instances.");
DEFINE_bool(test_secondary, false,
"If true, start an additional secondary instance which can be used "
"for verification.");
DEFINE_string(
expected_values_dir, "",
"Dir where files containing info about the latest/historical values will "
"be stored. If provided and non-empty, the DB state will be verified "
"against values from these files after recovery. --max_key and "
"--column_family must be kept the same across invocations of this program "
"that use the same --expected_values_dir. Currently historical values are "
"only tracked when --sync_fault_injection is set. See --seed and "
"--nooverwritepercent for further requirements.");
DEFINE_bool(verify_checksum, false,
"Verify checksum for every block read from storage");
DEFINE_bool(mmap_read, ROCKSDB_NAMESPACE::Options().allow_mmap_reads,
"Allow reads to occur via mmap-ing files");
DEFINE_bool(mmap_write, ROCKSDB_NAMESPACE::Options().allow_mmap_writes,
"Allow writes to occur via mmap-ing files");
DEFINE_bool(use_direct_reads, ROCKSDB_NAMESPACE::Options().use_direct_reads,
"Use O_DIRECT for reading data");
DEFINE_bool(use_direct_io_for_flush_and_compaction,
ROCKSDB_NAMESPACE::Options().use_direct_io_for_flush_and_compaction,
"Use O_DIRECT for writing data");
DEFINE_bool(mock_direct_io, false,
"Mock direct IO by not using O_DIRECT for direct IO read");
DEFINE_bool(statistics, false, "Create database statistics");
DEFINE_bool(sync, false, "Sync all writes to disk");
DEFINE_bool(use_fsync, false, "If true, issue fsync instead of fdatasync");
DEFINE_uint64(bytes_per_sync, ROCKSDB_NAMESPACE::Options().bytes_per_sync,
"If nonzero, sync SST file data incrementally after every "
"`bytes_per_sync` bytes are written");
DEFINE_uint64(wal_bytes_per_sync,
ROCKSDB_NAMESPACE::Options().wal_bytes_per_sync,
"If nonzero, sync WAL file data incrementally after every "
"`bytes_per_sync` bytes are written");
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 __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_kill_random_test, &ValidateInt32Positive);
DEFINE_string(kill_exclude_prefixes, "",
"If non-empty, kill points with prefix in the list given will be"
" skipped. Items are comma-separated.");
extern std::vector<std::string> rocksdb_kill_exclude_prefixes;
DEFINE_bool(disable_wal, false, "If true, do not write WAL for write.");
DEFINE_uint64(recycle_log_file_num,
ROCKSDB_NAMESPACE::Options().recycle_log_file_num,
"Number of old WAL files to keep around for later recycling");
DEFINE_int64(target_file_size_base,
ROCKSDB_NAMESPACE::Options().target_file_size_base,
"Target level-1 file size for compaction");
DEFINE_int32(target_file_size_multiplier, 1,
"A multiplier to compute target level-N file size (N >= 2)");
DEFINE_uint64(max_bytes_for_level_base,
ROCKSDB_NAMESPACE::Options().max_bytes_for_level_base,
"Max bytes for level-1");
DEFINE_double(max_bytes_for_level_multiplier, 2,
"A multiplier to compute max bytes for level-N (N >= 2)");
DEFINE_int32(range_deletion_width, 10,
"The width of the range deletion intervals.");
DEFINE_uint64(rate_limiter_bytes_per_sec, 0, "Set options.rate_limiter value.");
DEFINE_bool(rate_limit_bg_reads, false,
"Use options.rate_limiter on compaction reads");
DEFINE_bool(rate_limit_user_ops, false,
"When true use Env::IO_USER priority level to charge internal rate "
"limiter for reads associated with user operations.");
DEFINE_bool(rate_limit_auto_wal_flush, false,
"When true use Env::IO_USER priority level to charge internal rate "
"limiter for automatic WAL flush (`Options::manual_wal_flush` == "
"false) after the user "
"write operation.");
DEFINE_uint64(sst_file_manager_bytes_per_sec, 0,
"Set `Options::sst_file_manager` to delete at this rate. By "
"default the deletion rate is unbounded.");
DEFINE_uint64(sst_file_manager_bytes_per_truncate, 0,
"Set `Options::sst_file_manager` to delete in chunks of this "
"many bytes. By default whole files will be deleted.");
DEFINE_bool(use_txn, false,
"Use TransactionDB. Currently the default write policy is "
"TxnDBWritePolicy::WRITE_PREPARED");
DEFINE_uint64(txn_write_policy, 0,
"The transaction write policy. Default is "
"TxnDBWritePolicy::WRITE_COMMITTED. Note that this should not be "
"changed accross crashes.");
DEFINE_bool(unordered_write, false,
"Turn on the unordered_write feature. This options is currently "
"tested only in combination with use_txn=true and "
"txn_write_policy=TxnDBWritePolicy::WRITE_PREPARED.");
DEFINE_int32(backup_one_in, 0,
"If non-zero, then CreateNewBackup() will be called once for "
"every N operations on average. 0 indicates CreateNewBackup() "
"is disabled.");
DEFINE_uint64(backup_max_size, 100 * 1024 * 1024,
"If non-zero, skip checking backup/restore when DB size in "
"bytes exceeds this setting.");
DEFINE_int32(checkpoint_one_in, 0,
"If non-zero, then CreateCheckpoint() will be called once for "
"every N operations on average. 0 indicates CreateCheckpoint() "
"is disabled.");
DEFINE_int32(ingest_external_file_one_in, 0,
"If non-zero, then IngestExternalFile() will be called once for "
"every N operations on average. 0 indicates IngestExternalFile() "
"is disabled.");
DEFINE_int32(ingest_external_file_width, 100,
"The width of the ingested external files.");
DEFINE_int32(compact_files_one_in, 0,
"If non-zero, then CompactFiles() will be called once for every N "
"operations on average. 0 indicates CompactFiles() is disabled.");
DEFINE_int32(compact_range_one_in, 0,
"If non-zero, then CompactRange() will be called once for every N "
"operations on average. 0 indicates CompactRange() is disabled.");
DEFINE_int32(mark_for_compaction_one_file_in, 0,
"A `TablePropertiesCollectorFactory` will be registered, which "
"creates a `TablePropertiesCollector` with `NeedCompact()` "
"returning true once for every N files on average. 0 or negative "
"mean `NeedCompact()` always returns false.");
DEFINE_int32(flush_one_in, 0,
"If non-zero, then Flush() will be called once for every N ops "
"on average. 0 indicates calls to Flush() are disabled.");
DEFINE_int32(pause_background_one_in, 0,
"If non-zero, then PauseBackgroundWork()+Continue will be called "
"once for every N ops on average. 0 disables.");
DEFINE_int32(compact_range_width, 10000,
"The width of the ranges passed to CompactRange().");
DEFINE_int32(acquire_snapshot_one_in, 0,
"If non-zero, then acquires a snapshot once every N operations on "
"average.");
DEFINE_bool(compare_full_db_state_snapshot, false,
"If set we compare state of entire db (in one of the threads) with"
"each snapshot.");
DEFINE_uint64(snapshot_hold_ops, 0,
"If non-zero, then releases snapshots N operations after they're "
"acquired.");
DEFINE_bool(long_running_snapshots, false,
"If set, hold on some some snapshots for much longer time.");
DEFINE_bool(use_multiget, false,
"If set, use the batched MultiGet API for reads");
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 __attribute__((__unused__)) =
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 __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_prefixpercent, &ValidateInt32Percent);
DEFINE_int32(writepercent, 45,
"Ratio of writes to total workload (expressed as a percentage)");
static const bool FLAGS_writepercent_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_writepercent, &ValidateInt32Percent);
DEFINE_int32(delpercent, 15,
"Ratio of deletes to total workload (expressed as a percentage)");
static const bool FLAGS_delpercent_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_delpercent, &ValidateInt32Percent);
DEFINE_int32(delrangepercent, 0,
"Ratio of range deletions to total workload (expressed as a "
"percentage). Cannot be used with test_batches_snapshots");
static const bool FLAGS_delrangepercent_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_delrangepercent, &ValidateInt32Percent);
DEFINE_int32(nooverwritepercent, 60,
"Ratio of keys without overwrite to total workload (expressed as "
"a percentage). When --expected_values_dir is nonempty, must "
"keep this value constant across invocations.");
static const bool FLAGS_nooverwritepercent_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_nooverwritepercent, &ValidateInt32Percent);
DEFINE_int32(iterpercent, 10,
"Ratio of iterations to total workload"
" (expressed as a percentage)");
static const bool FLAGS_iterpercent_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_iterpercent, &ValidateInt32Percent);
DEFINE_uint64(num_iterations, 10, "Number of iterations per MultiIterate run");
static const bool FLAGS_num_iterations_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_num_iterations, &ValidateUint32Range);
DEFINE_int32(
customopspercent, 0,
"Ratio of custom operations to total workload (expressed as a percentage)");
DEFINE_string(compression_type, "snappy",
"Algorithm to use to compress the database");
DEFINE_int32(compression_max_dict_bytes, 0,
"Maximum size of dictionary used to prime the compression "
"library.");
DEFINE_int32(compression_zstd_max_train_bytes, 0,
"Maximum size of training data passed to zstd's dictionary "
"trainer.");
DEFINE_int32(compression_parallel_threads, 1,
"Number of threads for parallel compression.");
DEFINE_uint64(compression_max_dict_buffer_bytes, 0,
"Buffering limit for SST file data to sample for dictionary "
"compression.");
DEFINE_bool(
compression_use_zstd_dict_trainer, true,
"Use zstd's trainer to generate dictionary. If the options is false, "
"zstd's finalizeDictionary() API is used to generate dictionary. "
"ZSTD 1.4.5+ is required. If ZSTD 1.4.5+ is not linked with the binary, "
"this flag will have the default value true.");
DEFINE_string(bottommost_compression_type, "disable",
"Algorithm to use to compress bottommost level of the database. "
"\"disable\" means disabling the feature");
DEFINE_string(checksum_type, "kCRC32c", "Algorithm to use to checksum blocks");
DEFINE_string(env_uri, "",
"URI for env lookup. Mutually exclusive with --fs_uri");
DEFINE_string(fs_uri, "",
"URI for registry Filesystem lookup. Mutually exclusive"
" with --env_uri."
" Creates a default environment with the specified filesystem.");
DEFINE_uint64(ops_per_thread, 1200000, "Number of operations per thread.");
static const bool FLAGS_ops_per_thread_dummy __attribute__((__unused__)) =
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 __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_log2_keys_per_lock, &ValidateUint32Range);
DEFINE_uint64(max_manifest_file_size, 16384, "Maximum size of a MANIFEST file");
DEFINE_bool(in_place_update, false, "On true, does inplace update in memtable");
DEFINE_string(memtablerep, "skip_list", "");
inline static bool ValidatePrefixSize(const char* flagname, int32_t value) {
if (value < -1 || value > 8) {
fprintf(stderr, "Invalid value for --%s: %d. -1 <= PrefixSize <= 8\n",
flagname, value);
return false;
}
return true;
}
DEFINE_int32(prefix_size, 7,
"Control the prefix size for HashSkipListRep. "
"-1 is disabled.");
static const bool FLAGS_prefix_size_dummy __attribute__((__unused__)) =
RegisterFlagValidator(&FLAGS_prefix_size, &ValidatePrefixSize);
DEFINE_bool(use_merge, false,
"On true, replaces all writes with a Merge "
"that behaves like a Put");
DEFINE_bool(use_full_merge_v1, false,
"On true, use a merge operator that implement the deprecated "
"version of FullMerge");
DEFINE_int32(sync_wal_one_in, 0,
"If non-zero, then SyncWAL() will be called once for every N ops "
"on average. 0 indicates that calls to SyncWAL() are disabled.");
DEFINE_bool(avoid_unnecessary_blocking_io,
ROCKSDB_NAMESPACE::Options().avoid_unnecessary_blocking_io,
"If true, some expensive cleaning up operations will be moved from "
"user reads to high-pri background threads.");
DEFINE_bool(write_dbid_to_manifest,
ROCKSDB_NAMESPACE::Options().write_dbid_to_manifest,
"Write DB_ID to manifest");
DEFINE_bool(avoid_flush_during_recovery,
ROCKSDB_NAMESPACE::Options().avoid_flush_during_recovery,
"Avoid flush during recovery");
DEFINE_uint64(max_write_batch_group_size_bytes,
ROCKSDB_NAMESPACE::Options().max_write_batch_group_size_bytes,
"Max write batch group size");
DEFINE_bool(level_compaction_dynamic_level_bytes,
ROCKSDB_NAMESPACE::Options().level_compaction_dynamic_level_bytes,
"Use dynamic level");
DEFINE_int32(verify_checksum_one_in, 0,
"If non-zero, then DB::VerifyChecksum() will be called to do"
" checksum verification of all the files in the database once for"
" every N ops on average. 0 indicates that calls to"
" VerifyChecksum() are disabled.");
DEFINE_int32(verify_db_one_in, 0,
"If non-zero, call VerifyDb() once for every N ops. 0 indicates "
"that VerifyDb() will not be called in OperateDb(). Note that "
"enabling this can slow down tests.");
DEFINE_int32(continuous_verification_interval, 1000,
"While test is running, verify db every N milliseconds. 0 "
"disables continuous verification.");
DEFINE_int32(approximate_size_one_in, 64,
"If non-zero, DB::GetApproximateSizes() will be called against"
" random key ranges.");
DEFINE_int32(read_fault_one_in, 1000,
"On non-zero, enables fault injection on read");
DEFINE_int32(get_property_one_in, 1000,
"If non-zero, then DB::GetProperty() will be called to get various"
" properties for every N ops on average. 0 indicates that"
" GetProperty() will be not be called.");
DEFINE_bool(sync_fault_injection, false,
"If true, FaultInjectionTestFS will be used for write operations, "
"and unsynced data in DB will lost after crash. In such a case we "
"track DB changes in a trace file (\"*.trace\") in "
"--expected_values_dir for verifying there are no holes in the "
"recovered data.");
DEFINE_bool(best_efforts_recovery, false,
"If true, use best efforts recovery.");
DEFINE_bool(skip_verifydb, false, "If true, skip VerifyDb() calls.");
DEFINE_bool(enable_compaction_filter, false,
"If true, configures a compaction filter that returns a kRemove "
"decision for deleted keys.");
DEFINE_bool(paranoid_file_checks, true,
"After writing every SST file, reopen it and read all the keys "
"and validate checksums");
DEFINE_bool(fail_if_options_file_error, false,
"Fail operations that fail to detect or properly persist options "
"file.");
DEFINE_uint64(batch_protection_bytes_per_key, 0,
"If nonzero, enables integrity protection in `WriteBatch` at the "
"specified number of bytes per key. Currently the only supported "
"nonzero value is eight.");
DEFINE_string(file_checksum_impl, "none",
"Name of an implementation for file_checksum_gen_factory, or "
"\"none\" for null.");
DEFINE_int32(write_fault_one_in, 0,
"On non-zero, enables fault injection on write");
DEFINE_uint64(user_timestamp_size, 0,
"Number of bytes for a user-defined timestamp. Currently, only "
"8-byte is supported");
DEFINE_int32(open_metadata_write_fault_one_in, 0,
"On non-zero, enables fault injection on file metadata write "
"during DB reopen.");
#ifndef ROCKSDB_LITE
DEFINE_string(secondary_cache_uri, "",
"Full URI for creating a customized secondary cache object");
DEFINE_int32(secondary_cache_fault_one_in, 0,
"On non-zero, enables fault injection in secondary cache inserts"
" and lookups");
#endif // ROCKSDB_LITE
DEFINE_int32(open_write_fault_one_in, 0,
"On non-zero, enables fault injection on file writes "
"during DB reopen.");
DEFINE_int32(open_read_fault_one_in, 0,
"On non-zero, enables fault injection on file reads "
"during DB reopen.");
DEFINE_int32(injest_error_severity, 1,
"The severity of the injested IO Error. 1 is soft error (e.g. "
"retryable error), 2 is fatal error, and the default is "
"retryable error.");
DEFINE_int32(prepopulate_block_cache,
static_cast<int32_t>(ROCKSDB_NAMESPACE::BlockBasedTableOptions::
PrepopulateBlockCache::kDisable),
"Options related to cache warming (see `enum "
"PrepopulateBlockCache` in table.h)");
DEFINE_bool(two_write_queues, false,
"Set to true to enable two write queues. Default: false");
#ifndef ROCKSDB_LITE
DEFINE_bool(use_only_the_last_commit_time_batch_for_recovery, false,
"If true, the commit-time write batch will not be immediately "
"inserted into the memtables. Default: false");
DEFINE_uint64(
wp_snapshot_cache_bits, 7ull,
"Number of bits to represent write-prepared transaction db's snapshot "
"cache. Default: 7 (128 entries)");
DEFINE_uint64(wp_commit_cache_bits, 23ull,
"Number of bits to represent write-prepared transaction db's "
"commit cache. Default: 23 (8M entries)");
#endif // !ROCKSDB_LITE
DEFINE_bool(adaptive_readahead, false,
"Carry forward internal auto readahead size from one file to next "
"file at each level during iteration");
DEFINE_bool(
async_io, false,
"Does asynchronous prefetching when internal auto readahead is enabled");
DEFINE_string(wal_compression, "none",
"Algorithm to use for WAL compression. none to disable.");
DEFINE_bool(
verify_sst_unique_id_in_manifest, false,
"Enable DB options `verify_sst_unique_id_in_manifest`, if true, during "
"DB-open try verifying the SST unique id between MANIFEST and SST "
"properties.");
DEFINE_int32(
create_timestamped_snapshot_one_in, 0,
"On non-zero, create timestamped snapshots upon transaction commits.");
#endif // GFLAGS