Hey Andras, Thank you for your response.
I understand that mapreduce.job.classloader or mapreduce.user.classpath.first takes precendence over mapreduce.job.ubertask.enable. However why is this precedence enforced? What are the concerns? I could not find any details in the ticket. This is a blocker for us, since the configurations (mapreduce.job.classloader or mapreduce.user.classpath.first) are cluster wide and cannot be overridden at oozie server level. We could ideally override these properties at each workflow action level, however that would mean making changes to every running coordinator in the cluster. Thanks for pointing to the Oozie YARN ticket. However there seems to be many open issues as per https://issues.apache.org/jira/browse/OOZIE-2889. Also 5.0.0 not being GA, we cannot use it. Regards, Rohit On 6/6/17, 5:12 AM, "Andras Piros" <andras.pi...@cloudera.com> wrote: Hi Rohit, OOZIE-2123 <https://issues.apache.org/jira/browse/OOZIE-2123> is that when those parameters mapreduce.job.classloader or mapreduce.user.classpath.first are set by the user, they take precedence over oozie.action.launcher. mapreduce.job.ubertask.enable one - it will be silently set to false. The reasoning behind is that those parameters should have no effects when the Oozie launcher map-only MapTask runs in the same JVM of the YARN ApplicationMaster. Actually Oozie On YARN <https://issues.apache.org/jira/browse/OOZIE-1770> is already merged to master, meaning this uber job enable switch won't have an effect for the upcoming Oozie 5.0.0. As for how to influence YARN AM preemption, please see the CapacityScheduler documentation <https://hadoop.apache.org/docs/stable/hadoop-yarn/hadoop-yarn-site/CapacityScheduler.html>. on how to use yarn.scheduler.capacity.maximum-am-resource-percent. Regards, Andras On Mon, Jun 5, 2017 at 9:28 PM, Menon, Rohit <rme...@ea.com> wrote: > Hello, > > I had a query regarding https://issues.apache.org/jira/browse/OOZIE-2123. > > We want to enable uber mode for oozie launchers as a prerequisite for > preemption. However we do use mapreduce.user.classpath.first configuration > in our environment. What is the reasoning/concern behind disabling uber > mode when the above configuration is set? > > Any other suggestions for using preemption with oozie? > > We are using oozie 4.3.0 + Hadoop 2.7.3 > > Thanks, > Rohit >
