f48758e939
Summary: We found that the behavior of CompactionFilter::IgnoreSnapshots() = false isn't what we have expected. We thought that snapshot will always be preserved. However, we just realized that, if no snapshot is created while compaction starts, and a snapshot is created after that, the data seen from the snapshot can successfully be dropped by the compaction. This creates a strange behavior to the feature, which is hard to explain. Like what is documented in code comment, this feature is not very useful with snapshot anyway. The decision is to deprecate the feature. We keep the function to avoid to break users code. However, we will fail compactions if false is returned. Pull Request resolved: https://github.com/facebook/rocksdb/pull/4954 Differential Revision: D13981900 Pulled By: siying fbshipit-source-id: 2db8c2c3865acd86a28dca625945d1481b1d1e36
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.