rocksdb

fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph

Andrew Kryczka 6cac4c79d4 Fix race condition in db_stress checkpoint cleanup (#11389 ) Summary: The old cleanup code had a race condition: 1. Test thread: DestroyDB() marked a file as trash 2. DeleteScheduler thread: Got the file's size and decided to delete it in chunks 3. Test thread: DestroyDir() deleted that trash file 4. DeleteScheduler thread: Began deleting in chunks starting by calling ReopenWritableFile(). Unfortunately this recreates the deleted trash file 5. Test thread: DestroyDir() fails to remove the parent directory because it contains the file created in 4. 6. Test thread: Checkpoint::Create() fails due to the directory already existing It could be repro'd with the following patch/command. Patch: ``` diff --git a/file/delete_scheduler.cc b/file/delete_scheduler.cc index 8a2d1615d..337d24a60 100644 --- a/file/delete_scheduler.cc +++ b/file/delete_scheduler.cc @@ -317,6 +317,12 @@ Status DeleteScheduler::DeleteTrashFile(const std::string& path_in_trash, &num_hard_links, nullptr); if (my_status.ok()) { if (num_hard_links == 1) { + // Give some time for DestroyDir() to delete file entries. Then, the + // below `ReopenWritableFile()` will recreate files, preventing the + // parent directory from being deleted. + if (rand() % 2 == 0) { + usleep(1000); + } std::unique_ptr<FSWritableFile> wf; my_status = fs_->ReopenWritableFile(path_in_trash, FileOptions(), &wf, nullptr); diff --git a/file/file_util.cc b/file/file_util.cc index 43608fcdc..2cee1ad8e 100644 --- a/file/file_util.cc +++ b/file/file_util.cc @@ -263,6 +263,13 @@ Status DestroyDir(Env* env, const std::string& dir) { } } + // Give some time for the DeleteScheduler thread's ReopenWritableFile() to + // recreate deleted files + if (dir.find("checkpoint") != std::string::npos) { + fprintf(stderr, "waiting to destroy %s\n", dir.c_str()); + usleep(10000); + } + if (s.ok()) { s = env->DeleteDir(dir); // DeleteDir might or might not report NotFound ``` Command: ``` TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=131072 --target_file_size_base=131072 --max_bytes_for_level_base=524288 --checkpoint_one_in=100 --clear_column_family_one_in=0 --max_key=1000 --value_size_mult=33 --sst_file_manager_bytes_per_truncate=4096 --sst_file_manager_bytes_per_sec=1048576 --interval=3 --compression_type=none --sync_fault_injection=1 ``` Obviously we don't want to use scheduled deletion here as we need the checkpoint directory deleted immediately. I suspect the DestroyDir() was an attempt to fixup incomplete DestroyDB()s. Now that we expect DestroyDB() to be complete I removed that code. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11389 Reviewed By: hx235 Differential Revision: D45137142 Pulled By: ajkr fbshipit-source-id: 2af743d342c77cc414fd25fc4c9d7c9c6079ad24		2 years ago
.circleci	Revert enabling IO uring in db_stress (#11242 )	2 years ago
.github/workflows	ci: add GitHub token permissions for workflow (#10549 )	2 years ago
buckifier	Cleanup, improve, stress test LockWAL() (#11143 )	2 years ago
build_tools	Remove platform009 and default to platform010 (#11333 )	2 years ago
cache	fix bad implementation of ShardedCache::GetOccupancyCount (#11325 )	2 years ago
cmake	gcc-11 and cmake related cleanup (#9286 )	3 years ago
coverage	Remove platform009 and default to platform010 (#11333 )	2 years ago
db	Always allow L0->L1 trivial move during manual compaction (#11375 )	2 years ago
db_stress_tool	Fix race condition in db_stress checkpoint cleanup (#11389 )	2 years ago
docs	Remove docs/Gemfile.lock and update github-pages version (#11173 )	2 years ago
env	Ignore async_io ReadOption if FileSystem doesn't support it (#11296 )	2 years ago
examples	Remove RocksDB LITE (#11147 )	2 years ago
file	Ensure VerifyFileChecksums reads don't exceed readahead_size (#11328 )	2 years ago
fuzz	Add some missing headers (#10519 )	2 years ago
include/rocksdb	Block fetch CPU time counters in perf context (#11342 )	2 years ago
java	Set -source 8 in CMAKE_JAVA_COMPILE_FLAGS (#11385 )	2 years ago
logging	Disabling some IO error assertion in EnvLogger (#11314 )	2 years ago
memory	Remove RocksDB LITE (#11147 )	2 years ago
memtable	Add `SetAllowStall()` (#11335 )	2 years ago
microbench	Block fetch CPU time counters in perf context (#11342 )	2 years ago
monitoring	Block fetch CPU time counters in perf context (#11342 )	2 years ago
options	Initial add UDT in memtable only option (#11362 )	2 years ago
plugin	Add initial CMake support to plugin (#9214 )	3 years ago
port	Ignore async_io ReadOption if FileSystem doesn't support it (#11296 )	2 years ago
table	Update GeneralTableTest::ApproximateOffsetOfCompressed values (#11384 )	2 years ago
test_util	Try to pick more files in `LevelCompactionBuilder::TryExtendNonL0TrivialMove()` (#11347 )	2 years ago
third-party	fix optimization-disabled test builds with platform010 (#11361 )	2 years ago
tools	Change default block cache from 8MB to 32MB (#11350 )	2 years ago
trace_replay	Fix error maybe-uninitialized #11100 (#11101 )	2 years ago
util	util/ribbon_test.cc: avoid ambiguous reversed operator error in c++20 (#11371 )	2 years ago
utilities	Initial add UDT in memtable only option (#11362 )	2 years ago
.clang-format	A script that automatically reformat affected lines	11 years ago
.gitignore	Git ignore .clangd/ (#10817 )	2 years ago
.lgtm.yml	Create lgtm.yml for LGTM.com C/C++ analysis (#4058 )	7 years ago
.watchmanconfig	Added .watchmanconfig file to rocksdb repo (#5593 )	6 years ago
AUTHORS	Update RocksDB Authors File	7 years ago
CMakeLists.txt	New stat rocksdb.{cf\|db}-write-stall-stats exposed in a structural way (#11300 )	2 years ago
CODE_OF_CONDUCT.md	Adopt Contributor Covenant	5 years ago
CONTRIBUTING.md	Add Code of Conduct	7 years ago
COPYING	Add GPLv2 as an alternative license.	8 years ago
DEFAULT_OPTIONS_HISTORY.md	Add Options::DisableExtraChecks, clarify force_consistency_checks (#9363 )	3 years ago
DUMP_FORMAT.md	First version of rocksdb_dump and rocksdb_undump.	10 years ago
HISTORY.md	Always allow L0->L1 trivial move during manual compaction (#11375 )	2 years ago
INSTALL.md	Add instructions for installing googlebenchmark (#11282 )	2 years ago
LANGUAGE-BINDINGS.md	Add grocksdb in Go language bindings (#10498 )	2 years ago
LICENSE.Apache	Change RocksDB License	8 years ago
LICENSE.leveldb	Add back the LevelDB license file	8 years ago
Makefile	util/ribbon_test.cc: avoid ambiguous reversed operator error in c++20 (#11371 )	2 years ago
PLUGINS.md	Add pmem-rocksdb-plugin link in PLUGINs.md (#9934 )	3 years ago
README.md	Remove deprecated integration tests from README.md (#11354 )	2 years ago
TARGETS	New stat rocksdb.{cf\|db}-write-stall-stats exposed in a structural way (#11300 )	2 years ago
USERS.md	Add PaxosStore to USERS (#11357 )	2 years ago
Vagrantfile	Adding CentOS 7 Vagrantfile & build script	7 years ago
WINDOWS_PORT.md	Update branch name in WINDOWS_PORT.md (#8745 )	3 years ago
common.mk	Clean up variables for temporary directory (#9961 )	3 years ago
crash_test.mk	Allow a custom DB cleanup command to be passed to db_crashtest.py (#10883 )	2 years ago
issue_template.md	Add Google Group to Issue Template	5 years ago
rocksdb.pc.in	build: fix pkg-config file generation (#9953 )	3 years ago
src.mk	New stat rocksdb.{cf\|db}-write-stall-stats exposed in a structural way (#11300 )	2 years ago
thirdparty.inc	Fix build jemalloc api (#5470 )	6 years ago

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/main/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.

Questions and discussions are welcome on the RocksDB Developers Public Facebook group and email list on Google Groups.

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.