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Dave Latham commented on HBASE-3894: ------------------------------------ bq. Do we need HashedBytes? Was it you who said that wrapping the byte array in a ByteBuffer would do what we want? There's also a guava issue that may allow us to get rid of it at some point. http://code.google.com/p/guava-libraries/issues/detail?id=576 > Thread contention over row locks set monitor > -------------------------------------------- > > Key: HBASE-3894 > URL: https://issues.apache.org/jira/browse/HBASE-3894 > Project: HBase > Issue Type: Bug > Affects Versions: 0.90.2 > Reporter: Dave Latham > Priority: Blocker > Fix For: 0.90.4 > > Attachments: concurrentRowLocks-2.patch, > concurrentRowLocks-trunk.patch, > regionserver_rowLock_set_contention.threads.txt > > > HRegion maintains a set of row locks. Whenever any thread attempts to lock > or release a row it needs to acquire the monitor on that set. We've been > encountering cases with 30 handler threads all contending for that monitor, > blocked progress on the region server. Clients timeout, and retry making it > worse, and the region server stops responding to new clients almost entirely. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira