b278ae8e50
Summary: Use search hint to reduce FindFile range thus avoid comparison For a small DB with 50M keys, perf_context counter shows it reduces comparison from 2B to 1.3B for a 15-minute run. No perf change was observed for 1 seek thread, but quite good improvement was seen for 32 seek threads, when CPU was busy. will post detail results when ready Test Plan: db_bench and db_test Reviewers: haobo, sdong, dhruba, igor Reviewed By: igor Subscribers: leveldb Differential Revision: https://reviews.facebook.net/D18879
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 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/