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Wei-Chiu Chuang commented on HDFS-13594: ---------------------------------------- Is this still an issue after HDFS-14541 and HDFS-14535? > the lock of ShortCircuitCache is hold while close the ShortCircuitReplica > --------------------------------------------------------------------------- > > Key: HDFS-13594 > URL: https://issues.apache.org/jira/browse/HDFS-13594 > Project: Hadoop HDFS > Issue Type: Improvement > Components: hdfs-client > Affects Versions: 3.0.2 > Reporter: Gang Xie > Assignee: Lisheng Sun > Priority: Minor > Attachments: no_hdfs.svg > > > When we are profiling SC read, we find that ShortCircuitCache's lock is a hot > spot. After look into the code, we find that when close BlockReaderLocal, it > tries to trimEvictionMaps, and several ShortCircuitReplicas are closed while > the lock being hold. This slows down the close of the BlockReaderLocal, and > the worse is that it blocks the other allocating of the new > ShortCircuitReplicas. > An idea to avoid this is to close the replica in an async way. I will do a > prototype and get the performance. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org