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Hadoop QA commented on HADOOP-4780: ----------------------------------- -1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12396075/Hadoop-4780 against trunk revision 726129. +1 @author. The patch does not contain any @author tags. +1 tests included. The patch appears to include 3 new or modified tests. +1 javadoc. The javadoc tool did not generate any warning messages. +1 javac. The applied patch does not increase the total number of javac compiler warnings. -1 findbugs. The patch appears to introduce 1 new Findbugs warnings. +1 Eclipse classpath. The patch retains Eclipse classpath integrity. -1 core tests. The patch failed core unit tests. +1 contrib tests. The patch passed contrib unit tests. Test results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3746/testReport/ Findbugs warnings: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3746/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html Checkstyle results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3746/artifact/trunk/build/test/checkstyle-errors.html Console output: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3746/console This message is automatically generated. > Task Tracker burns a lot of cpu in calling getLocalCache > --------------------------------------------------------- > > Key: HADOOP-4780 > URL: https://issues.apache.org/jira/browse/HADOOP-4780 > Project: Hadoop Core > Issue Type: Bug > Components: mapred > Affects Versions: 0.19.0 > Reporter: Runping Qi > Assignee: he yongqiang > Fix For: 0.19.1 > > Attachments: Hadoop-4780 > > > I noticed that many times, a task tracker max up to 6 cpus. > During that time, iostat shows majority of that was system cpu. > That situation can last for quite long. > During that time, I saw a number of threads were in the following state: > java.lang.Thread.State: RUNNABLE > at java.io.UnixFileSystem.getBooleanAttributes0(Native Method) > at > java.io.UnixFileSystem.getBooleanAttributes(UnixFileSystem.java:228) > at java.io.File.exists(File.java:733) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:399) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at org.apache.hadoop.fs.FileUtil.getDU(FileUtil.java:407) > at > org.apache.hadoop.filecache.DistributedCache.getLocalCache(DistributedCache.java:176) > at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:140) > I suspect that getLocalCache is too expensive. > And calling it for every task initialization seems too much waste. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.