GitHub user shixiaogang opened a pull request: https://github.com/apache/flink/pull/3859
[FLINK-6504] [FLINK-6467] [checkpoints] Add needed synchronization for RocksDBIncrementalSnapshotOperation This pull request adds missing synchronization for the access to the following variables: 1. `materializedSstFiles` in `RocksDBKeyedStateBackend`: The variable may be accessed simultaneously by the processing thread (read) and the materialization threads (write). Now we use `asynchronousSnapshotLock` to prevent concurrent access. 2. `newSstFiles`, `oldSstFiles` and `metaStateHandle` in `RocksDBIncrementalSnapshotOperation`: These variables may be accessed by both the cancel thread and the materialization thread. Though the materialization thread are supposed to be stopped when `releaseResources()` is executed, we add synchronization here to prevent potential conflicts. You can merge this pull request into a Git repository by running: $ git pull https://github.com/shixiaogang/flink flink-6504 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/flink/pull/3859.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #3859 ---- commit 1c1a08e0f7db5ec8663a46c495468583983c7291 Author: xiaogang.sxg <xiaogang....@alibaba-inc.com> Date: 2017-05-10T01:55:34Z Add needed synchronization for RocksDBIncrementalSnapshotOperation ---- --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---