93f69cb93a
Summary: The previous compression type selection caused unexpected behavior when the base level was also the bottommost level. The following sequence of events could happen: - full compaction generates files with `bottommost_compression` type - now base level is bottommost level since all files are in the same level - any compaction causes files to be rewritten `compression_per_level` type since bottommost compression didn't apply to base level I changed the code to make bottommost compression apply to base level. Closes https://github.com/facebook/rocksdb/pull/3141 Differential Revision: D6264614 Pulled By: ajkr fbshipit-source-id: d7aaa8675126896684154a1f2c9034d6214fde82
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/