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Vinod Kumar Vavilapalli closed HDFS-8046. ----------------------------------------- > Allow better control of getContentSummary > ----------------------------------------- > > Key: HDFS-8046 > URL: https://issues.apache.org/jira/browse/HDFS-8046 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Kihwal Lee > Assignee: Kihwal Lee > Labels: 2.6.1-candidate, 2.7.2-candidate > Fix For: 2.6.1, 2.8.0, 2.7.2 > > Attachments: HDFS-8046-branch-2.6.1.txt, HDFS-8046.v1.patch > > > On busy clusters, users performing quota checks against a big directory > structure can affect the namenode performance. It has become a lot better > after HDFS-4995, but as clusters get bigger and busier, it is apparent that > we need finer grain control to avoid long read lock causing throughput drop. > Even with unfair namesystem lock setting, a long read lock (10s of > milliseconds) can starve many readers and especially writers. So the locking > duration should be reduced, which can be done by imposing a lower > count-per-iteration limit in the existing implementation. But HDFS-4995 came > with a fixed amount of sleep between locks. This needs to be made > configurable, so that {{getContentSummary()}} doesn't get exceedingly slow. -- This message was sent by Atlassian JIRA (v6.3.4#6332)