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Kihwal Lee commented on HDFS-12137: ----------------------------------- +1 the patch looks good. The test failure is not related. > DN dataset lock should be fair > ------------------------------ > > Key: HDFS-12137 > URL: https://issues.apache.org/jira/browse/HDFS-12137 > Project: Hadoop HDFS > Issue Type: Improvement > Components: datanode > Affects Versions: 2.8.0 > Reporter: Daryn Sharp > Assignee: Daryn Sharp > Priority: Critical > Attachments: HDFS-12137.branch-2.patch, HDFS-12137.trunk.patch, > HDFS-12137.trunk.patch > > > The dataset lock is very highly contended. The unfair nature can be > especially harmful to the heartbeat handling. Under high loads, partially > expose by HDFS-12136 introducing disk i/o within the lock, the heartbeat > handling thread may process commands so slowly due to the contention that the > node becomes stale or falsely declared dead. The unfair lock is not helping > and appears to be causing frequent starvation under load. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org