[ https://issues.apache.org/jira/browse/HADOOP-2247?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12553941 ]
Hadoop QA commented on HADOOP-2247: ----------------------------------- +1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12372075/HADOOP-2220.patch against trunk revision r606058. @author +1. The patch does not contain any @author tags. javadoc +1. The javadoc tool did not generate any warning messages. javac +1. The applied patch does not generate any new compiler warnings. findbugs +1. The patch does not introduce any new Findbugs warnings. core tests +1. The patch passed core unit tests. contrib tests +1. The patch passed contrib unit tests. Test results: http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1417/testReport/ Findbugs warnings: http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1417/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html Checkstyle results: http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1417/artifact/trunk/build/test/checkstyle-errors.html Console output: http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1417/console This message is automatically generated. > Mappers fail easily due to repeated failures > -------------------------------------------- > > Key: HADOOP-2247 > URL: https://issues.apache.org/jira/browse/HADOOP-2247 > Project: Hadoop > Issue Type: Bug > Affects Versions: 0.15.0 > Environment: 1400 Node hadoop cluster > Reporter: Srikanth Kakani > Assignee: Amar Kamat > Priority: Blocker > Fix For: 0.15.2 > > Attachments: HADOOP-2220.patch, HADOOP-2220.patch, HADOOP-2220.patch > > > Related to HADOOP-2220, problem introduced in HADOOP-1158 > At this scale hardcoding the number of fetch failures to a static number: in > this case 3 is never going to work. Although the jobs we are running are > loading the systems 3 failures can randomly occur within the lifetime of a > map. Even fetching the data can cause enough load for so many failures to > occur. > We believe that number of tasks and size of cluster should be taken into > account. Based on which we believe that a ratio between total fetch attempts > and total failed attempts should be taken into consideration. > Given our experience with a task should be declared "Too many fetch failures" > based on: > failures > n /*could be 3*/ && (failures/total attempts) > k% /*could be > 30-40%*/ > Basically the first factor is to give some headstart to the second factor, > second factor then takes into account the cluster size and the task size. > Additionally we could take recency into account, say failures and attempts in > last one hour. We do not want to make it too small. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.