[YARN-6917] Queue path is recomputed from scratch on every allocation

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.8.1
• Fix Version/s: 2.9.0, 3.0.0-beta1, 2.8.2
• Component/s: capacityscheduler
• Hadoop Flags: Reviewed
• Assignee: Eric Payne
• Reporter: Jason Darrell Lowe
• Created: 01/Aug/17 13:49
• Updated: 14/Aug/17 21:01
• Resolved: 14/Aug/17 20:46

Description

As part of the discussion in YARN-6901 I noticed that we are recomputing a queue's path for every allocation. Currently getting the queue's path involves calling getQueuePath on the parent then building onto that string with the basename of the queue. In turn the parent's getQueuePath method does the same, so we end up spending time recomputing a string that will never change until a reconfiguration.

Ideally the queue path should be computed once during queue initialization rather than on-demand.

Issue Links

• relates to: YARN-6901 A CapacityScheduler app->LeafQueue deadlock found in branch-2.8