2ed91622fb
Summary: Closes https://github.com/facebook/rocksdb/issues/1474 Helps show when the 12.5% threshold for GoodCompressionRatio (originally from ldb) is hit. Example output: ``` > ./sst_dump --file=/tmp/test.sst --command=recompress from [] to [] Process /tmp/test.sst Sst file format: block-based Block Size: 16384 Compression: kNoCompression Size: 122579836 Blocks: 2300 Compressed: 0 ( 0.0%) Not compressed (ratio): 2300 (100.0%) Not compressed (abort): 0 ( 0.0%) Compression: kSnappyCompression Size: 46289962 Blocks: 2300 Compressed: 2119 ( 92.1%) Not compressed (ratio): 181 ( 7.9%) Not compressed (abort): 0 ( 0.0%) Compression: kZlibCompression Size: 29689825 Blocks: 2300 Compressed: 2301 (100.0%) Not compressed (ratio): 0 ( 0.0%) Not compressed (abort): 0 ( 0.0%) Unsupported compression type: kBZip2Compression. Compression: kLZ4Compression Size: 44785490 Blocks: 2300 Compressed: 1950 ( 84.8%) Not compressed (ratio): 350 ( 15.2%) Not compressed (abort): 0 ( 0.0%) Compression: kLZ4HCCompression Size: 37498895 Blocks: 2300 Compressed: 2301 (100.0%) Not compressed (ratio): 0 ( 0.0%) Not compressed (abort): 0 ( 0.0%) Unsupported compression type: kXpressCompression. Compression: kZSTD Size: 32208707 Blocks: 2300 Compressed: 2301 (100.0%) Not compressed (ratio): 0 ( 0.0%) Not compressed (abort): 0 ( 0.0%) ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/5791 Differential Revision: D17347870 fbshipit-source-id: af10849c010b46b20e54162b70123c2805ffe526
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/
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.