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Hadoop QA commented on MAPREDUCE-5268: -------------------------------------- {color:green}+1 overall{color}. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12585626/mr-5268.patch against trunk revision . {color:green}+1 @author{color}. The patch does not contain any @author tags. {color:green}+1 tests included{color}. The patch appears to include 2 new or modified test files. {color:green}+1 javac{color}. The applied patch does not increase the total number of javac compiler warnings. {color:green}+1 javadoc{color}. The javadoc tool did not generate any warning messages. {color:green}+1 eclipse:eclipse{color}. The patch built with eclipse:eclipse. {color:green}+1 findbugs{color}. The patch does not introduce any new Findbugs (version 1.3.9) warnings. {color:green}+1 release audit{color}. The applied patch does not increase the total number of release audit warnings. {color:green}+1 core tests{color}. The patch passed unit tests in hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-hs. {color:green}+1 contrib tests{color}. The patch passed contrib unit tests. Test results: https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/3709//testReport/ Console output: https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/3709//console This message is automatically generated. > Improve history server startup performance > ------------------------------------------ > > Key: MAPREDUCE-5268 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-5268 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Components: jobhistoryserver > Affects Versions: 0.23.7, 2.0.4-alpha > Reporter: Jason Lowe > Assignee: Karthik Kambatla > Attachments: mr-5268.patch, mr-5268.patch, mr-5268.patch, > mr-5268.patch, mr-5268-prelim.patch > > > The history server can easily take many minutes to startup when there are a > significant number of jobs to scan in the done directory. However the > scanning of files is not the bottleneck, rather it's the heavy use of > ConcurrentSkipListMap.size in HistoryFileManager. > ConcurrentSkipListMap.size is a very expensive operation, especially on maps > with many entries, as it has to scan every entry to compute the size. We > should avoid calling this method or at least minimize its use. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira