GitHub user budde opened a pull request: https://github.com/apache/spark/pull/11012
[SPARK-13122] Fix race condition in MemoryStore.unrollSafely() https://issues.apache.org/jira/browse/SPARK-13122 A race condition can occur in MemoryStore's unrollSafely() method if two threads that return the same value for currentTaskAttemptId() execute this method concurrently. This change makes the operation of reading the initial amount of unroll memory used, performing the unroll, and updating the associated memory maps atomic in order to avoid this race condition. Initial proposed fix wraps all of unrollSafely() in a memoryManager.synchronized { } block. A cleaner approach might be introduce a mechanism that synchronizes based on task attempt ID. An alternative option might be to track unroll/pending unroll memory based on block ID rather than task attempt ID. You can merge this pull request into a Git repository by running: $ git pull https://github.com/budde/spark master Alternatively you can review and apply these changes as the patch at: https://github.com/apache/spark/pull/11012.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 #11012 ---- commit 6e0156c6e3c2fd137005ce3d55cecdf7070795da Author: Adam Budde <bu...@amazon.com> Date: 2016-02-02T01:04:45Z [SPARK-13122] Fix race condition in MemoryStore.unrollSafely() https://issues.apache.org/jira/browse/SPARK-13122 A race condition can occur in MemoryStore's unrollSafely() method if two threads that return the same value for currentTaskAttemptId() execute this method concurrently. This change makes the operation of reading the initial amount of unroll memory used, performing the unroll, and updating the associated memory maps atomic in order to avoid this race condition. ---- --- 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. --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org