Summary: Adding a light weight API to get last live WAL file name and size. Meant to be used as a helper for backup/restore tooling in a larger ecosystem such as MySQL with a MyRocks storage engine. Specifically within MySQL's backup/restore mechanism, this call can be made with a write lock on the mysql db to get a transactionally consistent snapshot of the current WAL file position along with other non-rocksdb log/data files. Without this, the alternative would be to take the aforementioned lock, scan the WAL dir for all files, find the last file and note its exact size as the rocksdb 'checkpoint'. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5765 Differential Revision: D17172717 Pulled By: affandar fbshipit-source-id: f2fabafd4c0e6fc45f126670c8c88a9f84cb8a37
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.