[MAPREDUCE-3631] Corner case in headroom calculation

• Type: Task
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 0.23.0
• Fix Version/s: 0.23.1
• Component/s: mrv2
• Assignee: Unassigned
• Reporter: Amol Kekre
• Created: 06/Jan/12 02:44
• Updated: 06/Jan/12 05:32
• Resolved: 06/Jan/12 05:32

Description

When there is a single queue and a large job fills up the whole cluster, a lost NM can lead to wrong headroom when all
slots are taken up by reduces since at that point headroom isn't recomputed.