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Yongjun Zhang commented on HDFS-6788: ------------------------------------- "I could" should read as "I wish":-) BTW, the failed test seems irrelevant to the patch here. thanks. > Improve synchronization in BPOfferService with read write lock > -------------------------------------------------------------- > > Key: HDFS-6788 > URL: https://issues.apache.org/jira/browse/HDFS-6788 > Project: Hadoop HDFS > Issue Type: Bug > Components: datanode > Affects Versions: 2.5.0 > Reporter: Yongjun Zhang > Assignee: Yongjun Zhang > Attachments: HDFS-6788.001.patch > > > Threads in DN (DataXceiver, PacketResponder, Async disk worker etc) may block > at BPOfferService.getBlockPoolId() when calling BPOfferService.checkBlock(), > though they are just reading the same blockpool id. This is unnecessary > overhead and may cause performance hit when many threads compete. Filing this > jira to replace synchronized method with read write lock > (ReentrantReadWriteLock). -- This message was sent by Atlassian JIRA (v6.2#6252)