CapacityScheduler infinite loop when queue is near fully utilized

ResourceManager does not respond to any request when queue is near fully utilized sometimes. Sending SIGTERM won't stop RM, only SIGKILL can. After RM restart, it can recover running jobs and start accepting new ones.

Seems like CapacityScheduler is in an infinite loop printing out the following log messages (more than 25,000 lines in a second):

2018-07-10 17:16:29,227 INFO org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.ParentQueue: assignedContainer queue=root usedCapacity=0.99816763 absoluteUsedCapacity=0.99816763 used=<memory:16170624, vCores:1577> cluster=<memory:29441544, vCores:5792>
2018-07-10 17:16:29,227 INFO org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler: Failed to accept allocation proposal
2018-07-10 17:16:29,227 INFO org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.allocator.AbstractContainerAllocator: assignedContainer application attempt=appattempt_1530619767030_1652_000001 container=null queue=org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.allocator.RegularContainerAllocator@14420943 clusterResource=<memory:29441544, vCores:5792> type=NODE_LOCAL requestedPartition=

I encounter this problem several times after upgrading to YARN 2.9.1, while the same configuration works fine under version 2.7.3.

YARN-4477 is an infinite loop bug in FairScheduler, not sure if this is a similar problem.