812dbfb483
Summary: Right now the way we do BlockIter::Prev() is like this - Go to the beginning of the restart interval - Keep moving forward (and decoding keys using ParseNextKey()) until we reach the desired key This can be optimized by caching the decoded entries in the first pass and reusing them in consecutive BlockIter::Prev() calls Before caching ``` DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readreverse" --db="/dev/shm/bench_prev_opt/" --use_existing_db --disable_auto_compactions DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.413 micros/op 2423972 ops/sec; 268.2 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.414 micros/op 2413867 ops/sec; 267.0 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.410 micros/op 2440881 ops/sec; 270.0 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.414 micros/op 2417298 ops/sec; 267.4 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.413 micros/op 2421682 ops/sec; 267.9 MB/s ``` After caching ``` DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readreverse" --db="/dev/shm/bench_prev_opt/" --use_existing_db --disable_auto_compactions DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.324 micros/op 3088955 ops/sec; 341.7 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.335 micros/op 2980999 ops/sec; 329.8 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.341 micros/op 2929681 ops/sec; 324.1 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.344 micros/op 2908490 ops/sec; 321.8 MB/s DB path: [/dev/shm/bench_prev_opt/] readreverse : 0.338 micros/op 2958404 ops/sec; 327.3 MB/s ``` Test Plan: COMPILE_WITH_ASAN=1 make check -j64 Reviewers: andrewkr, yiwu, sdong Reviewed By: sdong Subscribers: andrewkr, dhruba, yoshinorim Differential Revision: https://reviews.facebook.net/D59463 |
||
|---|---|---|
| arcanist_util | ||
| build_tools | ||
| coverage | ||
| db | ||
| doc | ||
| examples | ||
| hdfs | ||
| include/rocksdb | ||
| java | ||
| memtable | ||
| port | ||
| table | ||
| third-party | ||
| tools | ||
| util | ||
| utilities | ||
| .arcconfig | ||
| .clang-format | ||
| .gitignore | ||
| .travis.yml | ||
| appveyor.yml | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| DEFAULT_OPTIONS_HISTORY.md | ||
| DUMP_FORMAT.md | ||
| HISTORY.md | ||
| INSTALL.md | ||
| LANGUAGE-BINDINGS.md | ||
| LICENSE | ||
| Makefile | ||
| PATENTS | ||
| README.md | ||
| ROCKSDB_LITE.md | ||
| src.mk | ||
| thirdparty.inc | ||
| USERS.md | ||
| Vagrantfile | ||
| WINDOWS_PORT.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 specially 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/