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Hadoop QA commented on HDFS-3876: --------------------------------- +1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12543455/hdfs-3876.txt against trunk revision . +1 @author. The patch does not contain any @author tags. +1 tests included. The patch appears to include 3 new or modified test files. +1 javac. The applied patch does not increase the total number of javac compiler warnings. +1 javadoc. The javadoc tool did not generate any warning messages. +1 eclipse:eclipse. The patch built with eclipse:eclipse. +1 findbugs. The patch does not introduce any new Findbugs (version 1.3.9) warnings. +1 release audit. The applied patch does not increase the total number of release audit warnings. +1 core tests. The patch passed unit tests in hadoop-common-project/hadoop-common hadoop-hdfs-project/hadoop-hdfs. +1 contrib tests. The patch passed contrib unit tests. Test results: https://builds.apache.org/job/PreCommit-HDFS-Build/3138//testReport/ Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/3138//console This message is automatically generated. > NN should not RPC to self to find trash defaults (causes deadlock) > ------------------------------------------------------------------ > > Key: HDFS-3876 > URL: https://issues.apache.org/jira/browse/HDFS-3876 > Project: Hadoop HDFS > Issue Type: Bug > Components: name-node > Affects Versions: 2.2.0-alpha > Reporter: Todd Lipcon > Assignee: Eli Collins > Priority: Blocker > Attachments: hdfs-3876.txt, hdfs-3876.txt, hdfs-3876.txt > > > When transitioning a SBN to active, I ran into the following situation: > - the TrashPolicy first gets loaded by an IPC Server Handler thread. The > {{initialize}} function then tries to make an RPC to the same node to find > out the defaults. > - This is happening inside the NN write lock (since it's part of the active > initialization). Hence, all of the other handler threads are already blocked > waiting to get the NN lock. > - Since no handler threads are free, the RPC blocks forever and the NN never > enters active state. > We need to have a general policy that the NN should never make RPCs to itself > for any reason, due to potential for deadlocks like this. -- 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