4b41ccd2a7
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/15129 When `persist_user_defined_timestamps=false` and `long_running_snapshots=1`, `AssertSame` in `MaybeReleaseSnapshots` reuses the timestamp saved at snapshot acquisition time. That timestamp can become stale because concurrent flushes advance `full_history_ts_low`, and long-running snapshots can be held much longer than the 10-second headroom added by `GetReadTimestamp()`. The snapshot validation is intended to check that a held snapshot still exposes the same sequence-number view. It should not require the acquisition-time read timestamp to remain valid after history below `full_history_ts_low` has been collapsed. The fix keeps the timestamped read API contract intact. Column families with user-defined timestamps still require `ReadOptions.timestamp`, even when timestamps are memtable-only. For `persist_user_defined_timestamps=false`, `AssertSame` now uses a fresh validation timestamp so the read remains above `full_history_ts_low` while the snapshot sequence number continues to pin data visibility. For persisted timestamps, it continues reusing the original timestamp to validate the exact timestamped snapshot view. Reviewed By: joshkang97 Differential Revision: D116110124 fbshipit-source-id: 9cf6cae6e7123f8453b7065565e9e2e0eb34321a
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 especially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/main/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.
Questions and discussions are welcome on the RocksDB Developers Public Facebook group and email list on Google Groups.
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.