aeb4612685
Summary: There are currently no statistics on seeks, only on gets. This adds the following counters: rocksdb.number.db.seek rocksdb.number.db.next rocksdb.number.db.prev (number of calls) rocksdb.db.iterate.bytes.read (number of bytes read from key + value using seek/next/prev) rocksdb.number.keys.seek.found rocksdb.number.keys.next.found rocksdb.number.keys.prev.found (number of calls where seek/next/prev found a value) Test Plan: ./db_bench -statistics -benchmarks fillrandom,seekrandom -seek_nexts 5 ./db_bench -statistics -benchmarks fillrandom,seekrandom -seek_nexts 5 -reverse_iterator Reviewers: yhchiang, rven, kradhakrishnan, IslamAbdelRahman, MarkCallaghan, sdong, igor Reviewed By: sdong Subscribers: dhruba Differential Revision: https://reviews.facebook.net/D46605
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/