[MAPREDUCE-2219] JT should not try to remove mapred.system.dir during startup

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.22.0
• Fix Version/s: 0.22.0
• Component/s: jobtracker
• Hadoop Flags: Reviewed
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 15/Dec/10 22:11
• Updated: 12/Dec/11 06:19
• Resolved: 07/Jan/11 02:17

Description

During startup, the JT tries to clean up mapred.system.dir by recursively removing it and then recreating it. This requires that mapred.system.dir is inside a directory owned by the mapred user. For example, if set to /system/mapred then /system must be owned by the mapred account. This isn't documented properly and also seems unnecessary. Instead we can remove the contents of mapred.system.dir instead of the directory itself.