[YARN-7454] RMAppAttemptMetrics#getAggregateResourceUsage can NPE due to double lookup

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.1.0
• Fix Version/s: 3.0.0, 3.1.0
• Component/s: resourcemanager
• Target Version/s: 3.1.0
• Assignee: Jason Darrell Lowe
• Reporter: Jason Darrell Lowe
• Created: 07/Nov/17 15:52
• Updated: 09/Nov/17 16:03
• Resolved: 09/Nov/17 15:46

Description

RMAppAttemptMetrics#getAggregateResourceUsage does a double-lookup on a concurrent hash map, but the app could be removed from the map between the two lookups:

    RMApp rmApp = rmContext.getRMApps().get(attemptId.getApplicationId());
    if (rmApp != null) {
      RMAppAttempt currentAttempt = rmContext.getRMApps().get(attemptId.getApplicationId()).getCurrentAppAttempt();

The attempt should be looked up within rmApp directly rather than redundantly trying to retrieve the RMApp first.

Issue Links

• is broken by: YARN-6232 Update resource usage and preempted resource calculations to take into account all resource types