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ryantaocer commented on FLINK-10644: ------------------------------------ An initial design doc: https://docs.google.com/document/d/1X_Pfo4WcO-TEZmmVTTYNn44LQg5gnFeeaeqM7ZNLQ7M/edit?usp=sharing > Batch Job: Speculative execution > -------------------------------- > > Key: FLINK-10644 > URL: https://issues.apache.org/jira/browse/FLINK-10644 > Project: Flink > Issue Type: New Feature > Components: JobManager > Reporter: JIN SUN > Assignee: JIN SUN > Priority: Major > Fix For: 1.8.0 > > > Strugglers/outlier are tasks that run slower than most of the all tasks in a > Batch Job, this somehow impact job latency, as pretty much this straggler > will be in the critical path of the job and become as the bottleneck. > Tasks may be slow for various reasons, including hardware degradation, or > software mis-configuration, or noise neighboring. It's hard for JM to predict > the runtime. > To reduce the overhead of strugglers, other system such as Hadoop/Tez, Spark > has *_speculative execution_*. Speculative execution is a health-check > procedure that checks for tasks to be speculated, i.e. running slower in a > ExecutionJobVertex than the median of all successfully completed tasks in > that EJV, Such slow tasks will be re-submitted to another TM. It will not > stop the slow tasks, but run a new copy in parallel. And will kill the others > if one of them complete. > This JIRA is an umbrella to apply this kind of idea in FLINK. Details will be > append later. -- This message was sent by Atlassian JIRA (v7.6.3#76005)