ba16e8eee7
Summary: Before this PR, in `LevelCompactionBuilder::TryExtendNonL0TrivialMove(index)`, we start from a file at index and expand the compaction input towards right to find files to trivial move. This PR adds the logic to also expand towards left. Another major change made in this PR is to not expand L0 files through `TryExtendNonL0TrivialMove()`. This happens currently when compacting L0 files to an empty output level. The condition for expanding files in `TryExtendNonL0TrivialMove()` is to check atomic boundary, which does not take into account that L0 files can overlap in key range and are not sorted in key order. So it may include more L0 files than needed and disallow a trivial move. This change is included in this PR so that we don't make it worse by always expanding L0 in both direction. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11347 Test Plan: * new unit test * Benchmark does not show obvious improvement or regression: ``` Write sequentially ./db_bench --benchmarks=fillseq --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216 Main: fillseq : 4.726 micros/op 211592 ops/sec 472.607 seconds 100000000 operations; 23.4 MB/s This PR: fillseq : 4.755 micros/op 210289 ops/sec 475.534 seconds 100000000 operations; 23.3 MB/s Write randomly ./db_bench --benchmarks=fillrandom --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216 Main: fillrandom : 16.351 micros/op 61159 ops/sec 1635.066 seconds 100000000 operations; 6.8 MB/s This PR: fillrandom : 15.798 micros/op 63298 ops/sec 1579.817 seconds 100000000 operations; 7.0 MB/s ``` Reviewed By: ajkr Differential Revision: D44645650 Pulled By: cbi42 fbshipit-source-id: 8631f3a6b3f01decbbf18c34f2b62833cb4f9733 |
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buckifier | ||
build_tools | ||
cache | ||
cmake | ||
coverage | ||
db | ||
db_stress_tool | ||
docs | ||
env | ||
examples | ||
file | ||
fuzz | ||
include/rocksdb | ||
java | ||
logging | ||
memory | ||
memtable | ||
microbench | ||
monitoring | ||
options | ||
plugin | ||
port | ||
table | ||
test_util | ||
third-party | ||
tools | ||
trace_replay | ||
util | ||
utilities | ||
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.gitignore | ||
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.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 | ||
TARGETS | ||
USERS.md | ||
Vagrantfile | ||
WINDOWS_PORT.md | ||
common.mk | ||
crash_test.mk | ||
issue_template.md | ||
rocksdb.pc.in | ||
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/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.