[MAPREDUCE-5115] MR app master may try to assign a reduce priority container to a map

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Assignee: Unassigned
• Reporter: Bikas Saha
• Created: 28/Mar/13 21:33
• Updated: 28/Mar/13 21:43
• Resolved: 28/Mar/13 21:43

Description

ScheduledRequests.assign() checks reduces.isEmpty() and releases REDUCE priority containers. But it could have received more REDUCE priority containers than reduces.size() in which case it will not release excess REDUCE priority containers. Later on in ScheduledRequests.assignToReduce() it will not be able to assign them to reduces. These containers will fall through to ScheduledRequests.assignMapsWithLocality() where they will get assigned to maps or crash depending on the behavior of Java assert.

Issue Links

• duplicates: MAPREDUCE-5002 AM could potentially allocate a reduce container to a map attempt