ad81b654a4
Summary: Previously, during WAL replay, a secondary stored each 2PC prepare in `recovered_transactions_`. Replaying the matching commit or rollback marker deletes it. If the primary purges that marker's WAL before the secondary reads it, the prepared `WriteBatch` and its tracker entry remain until the secondary closes. This retention case was flagged by xingbowang in https://github.com/facebook/rocksdb/issues/15066. Even when the marker is replayed, the secondary records completion but previously did not prune the completed prefix from `logs_with_prep_tracker_`. This change deletes recovered transactions whose prepare WALs are all below `min_log_number_to_keep` after opening every discovered WAL reader but before replaying records. The primary keeps that watermark at or below every unresolved prepare and every prepare with unflushed committed data, so an entry below it is committed and flushed, or rolled back. Deleting before replay lets a reused transaction name start a new generation instead of merging into stale state. If a reader cannot be opened, no recovered transaction is deleted. After a round successfully replays every discovered WAL, the secondary also prunes the completed prefix from `logs_with_prep_tracker_`. This covers completions from normal commit or rollback replay and from the watermark-based cleanup. The oldest outstanding prepare stops the pruning scan. Pull Request resolved: https://github.com/facebook/rocksdb/pull/15121 Test Plan: Added coverage for missed-marker cleanup, transaction-name reuse before replay, the exact watermark boundary, a catch-up round that reports success after replaying no WALs, and tracker pruning after normal commit replay. The missed-marker case verifies cleanup of both retained structures. Reviewed By: pdillinger Differential Revision: D116620460 Pulled By: xingbowang fbshipit-source-id: baca7faf53f414507957f2afdcc4ca67133c5669
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.