7d3eb006ff
Summary: When a CompactRange() call for a level is truncated before the end key is reached, because it exceeds max_compaction_bytes, we need to properly set the compaction_end parameter to indicate the stop key. The next CompactRange will use that as the begin key. We set it to the smallest key of the next file in the level after expanding inputs to get a clean cut. Previously, we were setting it before expanding inputs. So we could end up recompacting some files. In a pathological case, where a single key has many entries spanning all the files in the level (possibly due to merge operands without a partial merge operator, thus resulting in compaction output identical to the input), this would result in an endless loop over the same set of files. Pull Request resolved: https://github.com/facebook/rocksdb/pull/4496 Differential Revision: D10395026 Pulled By: anand1976 fbshipit-source-id: f0c2f89fee29b4b3be53b6467b53abba8e9146a9
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.