[HBASE-7633] Add a metric that tracks the current number of used RPC threads on the regionservers

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Component/s: metrics
• Assignee: Elliott Neil Clark
• Reporter: Joey Echeverria
• Created: 21/Jan/13 15:01
• Updated: 16/Jun/22 01:18
• Resolved: 15/Aug/13 21:06

Description

One way to detect that you're hitting a "John Wayne" disk[1] would be if we could see when region servers exhausted their RPC handlers. This would also be useful when tuning the cluster for your workload to make sure that reads or writes were not starving the other operations out.

[1] http://hbase.apache.org/book.html#bad.disk