b278152261
Summary: The db_stress crash was caused by a call to `IsFlushPending()` made by a stats function which triggered an `assert([false])`, which I didn't plan when I created the `trigger_flush` bool. It turns out that this bool variable is not useful: I created it because I thought the `imm_flush_needed` atomic bool would actually trigger a flush. It turns out that this bool is only checked in `IsFlushPending` - this is its only use - and a flush is triggered by either a background thread checking on the imm array, or by an explicit call to `SchedulePendingFlush` which creates a flush request, that is then added to a flush request queue. In this PR, I reverted the MemtableList::Add function to what it was before my changes. I tested the fix by running the exact command line that deterministically triggered the assert error (see below), which confirmed that this is where the error was coming from. I also run `db_crashtest.py whitebox` and `blackbox` for a couple hours locally before committing this PR. Experiment run: ```./db_stress --acquire_snapshot_one_in=0 --allow_concurrent_memtable_write=1 --avoid_flush_during_recovery=0 --avoid_unnecessary_blocking_io=1 --backup_max_size=104857600 --backup_one_in=100000 --batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=76.90653425292307 --bottommost_compression_type=disable --cache_index_and_filter_blocks=1 --cache_size=1048576 --checkpoint_one_in=1000000 --checksum_type=kCRC32c --clear_column_family_one_in=0 --column_families=1 --compact_files_one_in=1000000 --compact_range_one_in=0 --compaction_ttl=2 --compression_max_dict_buffer_bytes=0 --compression_max_dict_bytes=0 --compression_parallel_threads=1 --compression_type=zstd --compression_zstd_max_train_bytes=0 --continuous_verification_interval=0 --db=/dev/shm/rocksdb/rocksdb_crashtest_blackbox --db_write_buffer_size=0 --delpercent=4 --delrangepercent=1 --destroy_db_initially=0 --enable_compaction_filter=1 --enable_pipelined_write=0 --expected_values_path=/dev/shm/rocksdb/rocksdb_crashtest_expected --experimental_allow_mempurge=1 --experimental_mempurge_policy=kAlternate --fail_if_options_file_error=1 --file_checksum_impl=none --flush_one_in=1000000 --format_version=2 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=14 --index_type=0 --iterpercent=0 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=False --long_running_snapshots=1 --mark_for_compaction_one_file_in=10 --max_background_compactions=1 --max_bytes_for_level_base=67108864 --max_key=100000000 --max_key_len=3 --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=64 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=0 --memtablerep=skip_list --mmap_read=0 --mock_direct_io=True --nooverwritepercent=1 --open_files=-1 --open_metadata_write_fault_one_in=8 --open_read_fault_one_in=32 --open_write_fault_one_in=16 --ops_per_thread=100000000 --optimize_filters_for_memory=1 --paranoid_file_checks=0 --partition_filters=0 --partition_pinning=0 --pause_background_one_in=1000000 --periodic_compaction_seconds=1000 --prefix_size=-1 --prefixpercent=0 --progress_reports=0 --read_fault_one_in=0 --readpercent=60 --recycle_log_file_num=1 --reopen=20 --set_options_one_in=0 --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=104857600 --sst_file_manager_bytes_per_truncate=0 --subcompactions=3 --sync=1 --sync_fault_injection=False --target_file_size_base=16777216 --target_file_size_multiplier=1 --test_batches_snapshots=0 --top_level_index_pinning=1 --unpartitioned_pinning=3 --use_clock_cache=0 --use_direct_io_for_flush_and_compaction=1 --use_direct_reads=0 --use_full_merge_v1=1 --use_merge=0 --use_multiget=0 --use_ribbon_filter=1 --user_timestamp_size=0 --verify_checksum=1 --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --write_buffer_size=33554432 --write_dbid_to_manifest=1 --writepercent=35``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/8604 Reviewed By: pdillinger Differential Revision: D30047295 Pulled By: bjlemaire fbshipit-source-id: b9e379bfa3d6b9bd2b275725fb0bca4bd81a3dbe |
||
---|---|---|
.circleci | ||
.github/workflows | ||
buckifier | ||
build_tools | ||
cache | ||
cmake | ||
coverage | ||
db | ||
db_stress_tool | ||
docs | ||
env | ||
examples | ||
file | ||
fuzz | ||
hdfs | ||
include/rocksdb | ||
java | ||
logging | ||
memory | ||
memtable | ||
microbench | ||
monitoring | ||
options | ||
plugin | ||
port | ||
table | ||
test_util | ||
third-party | ||
tools | ||
trace_replay | ||
util | ||
utilities | ||
.clang-format | ||
.gitignore | ||
.lgtm.yml | ||
.travis.yml | ||
.watchmanconfig | ||
AUTHORS | ||
CMakeLists.txt | ||
CODE_OF_CONDUCT.md | ||
CONTRIBUTING.md | ||
COPYING | ||
DEFAULT_OPTIONS_HISTORY.md | ||
DUMP_FORMAT.md | ||
HISTORY.md | ||
INSTALL.md | ||
LANGUAGE-BINDINGS.md | ||
LICENSE.Apache | ||
LICENSE.leveldb | ||
Makefile | ||
PLUGINS.md | ||
README.md | ||
ROCKSDB_LITE.md | ||
TARGETS | ||
USERS.md | ||
Vagrantfile | ||
WINDOWS_PORT.md | ||
appveyor.yml | ||
defs.bzl | ||
issue_template.md | ||
src.mk | ||
thirdparty.inc |
README.md
RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)
This code is a library that forms the core building block for a fast key-value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it especially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples
See the github wiki for more explanation.
The public interface is in include/
. Callers should not include or
rely on the details of any other header files in this package. Those
internal APIs may be changed without warning.
Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/ and https://rocksdb.slack.com/
License
RocksDB is dual-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). You may select, at your option, one of the above-listed licenses.