Yanqin Jin 671a7eb36f Avoid switching empty memtable in certain cases (#4792)
Summary:
in certain cases, we do not perform memtable switching if the active
memtable of the column family is empty. Two exceptions:
1. In manual flush, if cached_recoverable_state_empty_ is false, then we need
   to switch memtable due to requirement of transaction.
2. In switch WAL, we need to switch memtable anyway because we have to seal the
   memtable if the WAL on which it depends will be closed.

This change can potentially delay the occurence of write stalls because number
of memtables increase more slowly.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4792

Differential Revision: D13499501

Pulled By: riversand963

fbshipit-source-id: 91c9b17ae753578578039f3851667d93610005e1
2018-12-18 16:47:23 -08:00
2018-11-21 20:28:03 -08:00
2018-08-13 11:44:02 -07:00
2018-02-01 13:57:01 -08:00
2017-10-18 14:42:10 -07:00
2017-12-05 18:42:35 -08:00
2017-12-05 18:42:35 -08:00
2017-04-27 18:06:12 -07:00
2018-03-19 12:30:05 -07:00
2017-09-29 11:41:28 -07:00
2017-07-15 16:11:23 -07:00
2018-12-17 17:33:46 -08:00
2018-12-17 17:33:46 -08:00
2018-12-17 17:33:46 -08:00
2018-07-13 10:58:06 -07:00

RocksDB: A Persistent Key-Value Store for Flash and RAM Storage

Linux/Mac Build Status Windows Build status PPC64le Build Status

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.

Description
A library that provides an embeddable, persistent key-value store for fast storage.
Readme 271 MiB
Languages
C++ 82.1%
Java 10.3%
C 2.5%
Python 1.7%
Perl 1.1%
Other 2.1%