[HBASE-17205] Add a metric for the duration of region in transition

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.4.0, 2.0.0
• Fix Version/s: 1.4.0, 1.3.3, 2.0.0
• Component/s: Region Assignment
• Assignee: Guanghao Zhang
• Reporter: Guanghao Zhang
• Created: 30/Nov/16 10:48
• Updated: 14/Dec/18 10:08
• Resolved: 01/Dec/16 18:37

Description

When work for HBASE-17178, I found there are not a metric for the overall duration of region in transition. When move a region form A to B, the transformation of region state is PENDING_CLOSE => CLOSING => CLOSED => PENDING_OPEN => OPENING => OPENED. When transform old region state to new region state, it update the time stamp to current time. So we can't get the overall transformation's duration of region in transition. Add a rit duration to RegionState for accumulating this metric.