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 >
