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Konstantin Shvachko commented on MAPREDUCE-2026: ------------------------------------------------ Scot, Joydeep. This seems to be an important fix for 0.22. Do you think it is ready to be committed? > JobTracker.getJobCounters() should not hold JobTracker lock while calling > JobInProgress.getCounters() > ----------------------------------------------------------------------------------------------------- > > Key: MAPREDUCE-2026 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-2026 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Reporter: Scott Chen > Assignee: Joydeep Sen Sarma > Attachments: 2026.1.patch, MAPREDUCE-2026.txt > > > JobTracker.getJobCounter() will lock JobTracker and call > JobInProgress.getCounters(). > JobInProgress.getCounters() can be very expensive because it aggregates all > the task counters. > We found that from the JobTracker jstacks that this method is one of the > bottleneck of the JobTracker performance. > JobInProgress.getCounters() should be able to be called out side the > JobTracker lock because it already has JobInProgress lock. > For example, it is used by jobdetails.jsp without a JobTracker lock. -- This message is automatically generated by JIRA. - For more information on JIRA, see: http://www.atlassian.com/software/jira