09528f9fa1
Summary: According to https://github.com/facebook/rocksdb/issues/5907, each filter partition "should include the bloom of the prefix of the last key in the previous partition" so that SeekForPrev() in prefix mode can return correct result. The prefix of the last key in the previous partition does not necessarily have the same prefix as the first key in the current partition. Regardless of the first key in current partition, the prefix of the last key in the previous partition should be added. The existing code, however, does not follow this. Furthermore, there is another issue: when finishing current filter partition, `FullFilterBlockBuilder::AddPrefix()` is called for the first key in next filter partition, which effectively overwrites `last_prefix_str_` prematurely. Consequently, when the filter block builder proceeds to the next partition, `last_prefix_str_` will be the prefix of its first key, leaving no way of adding the bloom of the prefix of the last key of the previous partition. Prefix extractor is FixedLength.2. ``` [ filter part 1 ] [ filter part 2 ] abc d ``` When SeekForPrev("abcd"), checking the filter partition will land on filter part 2 because "abcd" > "abc" but smaller than "d". If the filter in filter part 2 happens to return false for the test for "ab", then SeekForPrev("abcd") will build incorrect iterator tree in non-total-order mode. Also fix a unit test which starts to fail following this PR. `InDomain` should not fail due to assertion error when checking on an arbitrary key. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8137 Test Plan: ``` make check ``` Without this fix, the following command will fail pretty soon. ``` ./db_stress --acquire_snapshot_one_in=10000 --avoid_flush_during_recovery=0 \ --avoid_unnecessary_blocking_io=0 --backup_max_size=104857600 --backup_one_in=0 \ --batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=17 \ --bottommost_compression_type=disable --cache_index_and_filter_blocks=1 --cache_size=1048576 \ --checkpoint_one_in=0 --checksum_type=kxxHash64 --clear_column_family_one_in=0 \ --compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_ttl=0 \ --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_whitebox \ --db_write_buffer_size=8388608 --delpercent=5 --delrangepercent=0 --destroy_db_initially=0 --enable_blob_files=0 \ --enable_compaction_filter=0 --enable_pipelined_write=1 --file_checksum_impl=big --flush_one_in=1000000 \ --format_version=5 --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=4 --index_type=2 --ingest_external_file_one_in=0 \ --iterpercent=10 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=True \ --log2_keys_per_lock=10 --long_running_snapshots=1 --mark_for_compaction_one_file_in=0 \ --max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=100000000 --max_key_len=3 \ --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=16777216 --max_write_buffer_number=3 \ --max_write_buffer_size_to_maintain=8388608 --memtablerep=skip_list --mmap_read=1 --mock_direct_io=False \ --nooverwritepercent=0 --open_files=500000 --ops_per_thread=20000000 --optimize_filters_for_memory=0 --paranoid_file_checks=1 --partition_filters=1 --partition_pinning=0 --pause_background_one_in=1000000 \ --periodic_compaction_seconds=0 --prefixpercent=5 --progress_reports=0 --read_fault_one_in=0 --read_only=0 \ --readpercent=45 --recycle_log_file_num=0 --reopen=20 --secondary_catch_up_one_in=0 \ --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=104857600 \ --sst_file_manager_bytes_per_truncate=0 --subcompactions=2 --sync=0 --sync_fault_injection=False \ --target_file_size_base=2097152 --target_file_size_multiplier=2 --test_batches_snapshots=0 --test_cf_consistency=0 \ --top_level_index_pinning=0 --unpartitioned_pinning=1 --use_blob_db=0 --use_block_based_filter=0 \ --use_direct_io_for_flush_and_compaction=0 --use_direct_reads=0 --use_full_merge_v1=0 --use_merge=0 \ --use_multiget=0 --use_ribbon_filter=0 --use_txn=0 --user_timestamp_size=8 --verify_checksum=1 \ --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --write_buffer_size=4194304 \ --write_dbid_to_manifest=1 --writepercent=35 ``` Reviewed By: pdillinger Differential Revision: D27553054 Pulled By: riversand963 fbshipit-source-id: 60e391e4a2d8d98a9a3172ec5d6176b90ec3de98 |
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buckifier | ||
build_tools | ||
cache | ||
cmake | ||
coverage | ||
db | ||
db_stress_tool | ||
docs | ||
env | ||
examples | ||
file | ||
fuzz | ||
hdfs | ||
include/rocksdb | ||
java | ||
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memory | ||
memtable | ||
monitoring | ||
options | ||
plugin | ||
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table | ||
test_util | ||
third-party | ||
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trace_replay | ||
util | ||
utilities | ||
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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.