[HADOOP-3753] metrics: FileContext support overwrite mode

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Incomplete
• Component/s: metrics
• Assignee: Unassigned
• Reporter: Craig Macdonald
• Created: 13/Jul/08 16:39
• Updated: 18/Jul/14 18:00
• Resolved: 18/Jul/14 18:00

Description

FileContext currently continually appends to the metrics log file(s), generating an ever lengthening file.

In some scenarios, it would be useful to simply write the current statistics to the file once every period, then overwrite the file for the next period.

For instance, this could be useful if an external application parsed the metrics output - e.g. Cacti to create realtime graphs.