[YARN-2124] ProportionalCapacityPreemptionPolicy cannot work because it's initialized before scheduler initialized

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 3.0.0-alpha1
• Fix Version/s: 2.5.0
• Component/s: resourcemanager, scheduler
• Target Version/s: 2.5.0
• Hadoop Flags: Reviewed
• Assignee: Wangda Tan
• Reporter: Wangda Tan
• Created: 05/Jun/14 07:44
• Updated: 12/May/16 18:30
• Resolved: 11/Jun/14 17:32

Description

When I play with scheduler with preemption, I found ProportionalCapacityPreemptionPolicy cannot work. NPE will be raised when RM start

2014-06-05 11:01:33,201 ERROR org.apache.hadoop.yarn.YarnUncaughtExceptionHandler: Thread Thread[SchedulingMonitor (ProportionalCapacityPreemptionPolicy),5,main] threw an Exception.
java.lang.NullPointerException
        at org.apache.hadoop.yarn.util.resource.Resources.greaterThan(Resources.java:225)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.capacity.ProportionalCapacityPreemptionPolicy.computeIdealResourceDistribution(ProportionalCapacityPreemptionPolicy.java:302)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.capacity.ProportionalCapacityPreemptionPolicy.recursivelyComputeIdealAssignment(ProportionalCapacityPreemptionPolicy.java:261)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.capacity.ProportionalCapacityPreemptionPolicy.containerBasedPreemptOrKill(ProportionalCapacityPreemptionPolicy.java:198)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.capacity.ProportionalCapacityPreemptionPolicy.editSchedule(ProportionalCapacityPreemptionPolicy.java:174)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.SchedulingMonitor.invokePolicy(SchedulingMonitor.java:72)
        at org.apache.hadoop.yarn.server.resourcemanager.monitor.SchedulingMonitor$PreemptionChecker.run(SchedulingMonitor.java:82)
        at java.lang.Thread.run(Thread.java:744)

This is caused by ProportionalCapacityPreemptionPolicy needs ResourceCalculator from CapacityScheduler. But ProportionalCapacityPreemptionPolicy get initialized before CapacityScheduler initialized. So ResourceCalculator will set to null in ProportionalCapacityPreemptionPolicy.