[ https://issues.apache.org/jira/browse/HADOOP-4232?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Devaraj Das updated HADOOP-4232: -------------------------------- Status: Patch Available (was: Open) Passing through hudson > Race condition in JVM reuse when more than one slot becomes free > ---------------------------------------------------------------- > > Key: HADOOP-4232 > URL: https://issues.apache.org/jira/browse/HADOOP-4232 > Project: Hadoop Core > Issue Type: Bug > Components: mapred > Affects Versions: 0.19.0 > Reporter: Devaraj Das > Assignee: Devaraj Das > Priority: Blocker > Fix For: 0.19.0 > > Attachments: 4232.patch > > > A race condition exists where there are two or more slots free and there are > two or more tasks waiting to run. As an example, consider a case where there > are two free slots and there are two tasks waiting to run. JVM_job1 and > JVM_job2 are the two idle jvms in memory. A waiting task, task job1_t1, kills > the JVM_job2 and spawns a new one, JVM_1_job1. While JVM_1_job1 is > initializing (it is marked busy during initialization), JVM_job1 picks this > task up and hence this becomes busy as well. Another waiting task, job3_t1 > finds both the JVMs busy and doesn't spawn a new JVM. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.