[ https://issues.apache.org/jira/browse/SPARK-47819?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Xi Lyu updated SPARK-47819: --------------------------- Description: Expired sessions are regularly checked and cleaned up by a maintenance thread. However, currently, this process is synchronous. Therefore, in rare cases, interrupting the execution thread of a query in a session can take hours, causing the entire maintenance process to stall, resulting in a large amount of memory not being cleared. We address this by introducing asynchronous callbacks for execution cleanup, avoiding synchronous joins of execution threads, and preventing the maintenance thread from stalling in the above scenarios. To be more specific, instead of calling {{runner.join()}} in ExecutorHolder.close(), we set a post-cleanup function as the callback through {{{}runner.processOnCompletion{}}}, which will be called asynchronously once the execution runner is completed or interrupted. In this way, the maintenance thread won't get blocked on {{{}join{}}}ing an execution thread. was: Expired sessions are regularly checked and cleaned up by a maintenance thread. However, currently, this process is synchronous. Therefore, in occasional cases, interrupting the execution thread of a query in a session can take hours, causing the entire maintenance process to stall, resulting in a large amount of memory not being cleared. We address this by introducing asynchronous callbacks for execution cleanup, avoiding synchronous joins of execution threads, and preventing the maintenance thread from stalling in the above occasional scenarios. To be more specific, instead of calling {{runner.join()}} in ExecutorHolder.close(), we set a post-cleanup function as the callback through {{{}runner.processOnCompletion{}}}, which will be called asynchronously once the execution runner is completed or interrupted. In this way, the maintenance thread won't get blocked on {{{}join{}}}ing an execution thread. > Use asynchronous callback for execution cleanup > ----------------------------------------------- > > Key: SPARK-47819 > URL: https://issues.apache.org/jira/browse/SPARK-47819 > Project: Spark > Issue Type: Improvement > Components: Connect > Affects Versions: 4.0.0 > Reporter: Xi Lyu > Priority: Major > Fix For: 4.0.0 > > > Expired sessions are regularly checked and cleaned up by a maintenance > thread. However, currently, this process is synchronous. Therefore, in rare > cases, interrupting the execution thread of a query in a session can take > hours, causing the entire maintenance process to stall, resulting in a large > amount of memory not being cleared. > We address this by introducing asynchronous callbacks for execution cleanup, > avoiding synchronous joins of execution threads, and preventing the > maintenance thread from stalling in the above scenarios. To be more specific, > instead of calling {{runner.join()}} in ExecutorHolder.close(), we set a > post-cleanup function as the callback through > {{{}runner.processOnCompletion{}}}, which will be called asynchronously once > the execution runner is completed or interrupted. In this way, the > maintenance thread won't get blocked on {{{}join{}}}ing an execution thread. > -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org