df74b775e6
Summary: This was requested by a customer who wants to proactively monitor whether any valid backups are available. The existing performance was poor because Open() serially reads every small meta-file (one per backup), which was slow on HDFS. Now we only read the minimum number of meta-files to find `max_valid_backups_to_open` valid backups. The customer mentioned above can just set it to one. Closes https://github.com/facebook/rocksdb/pull/2151 Differential Revision: D4882564 Pulled By: ajkr fbshipit-source-id: cb0edf9e8ac693e4d5f24902e725a011ed8c0c2f
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/