[MAPREDUCE-2345] Optimize jobtracker's memory usage

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 0.21.0
• Component/s: jobtracker
• Labels: hadoop
• Assignee: Unassigned
• Reporter: MengWang
• Created: 25/Feb/11 03:25
• Updated: 09/Mar/15 22:48
• Resolved: 09/Mar/15 22:48

Description

Too many tasks will eat up a considerable amount of JobTracker's heap space. According to our observation, 50GB heap size can support to 5,000,000 tasks, so we should optimize jobtracker's memory usage for more jobs and tasks. Yourkit java profile show that counters, duplicate strings, task waste too much memory. Our optimization around these three points reduced jobtracker's memory to 1/3.