[HDFS-15808] Add metrics for FSNamesystem read/write lock hold long time

• Type: Wish
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.3.1, 3.4.0, 2.10.2, 3.2.3
• Component/s: hdfs
• Labels: hdfs lock metrics pull-request-available
• Hadoop Flags: Reviewed
• External issue URL: https://github.com/apache/hadoop/pull/2668#issue-565150882
• Assignee: Tao Li
• Reporter: Tao Li
• Created: 01/Feb/21 12:36
• Updated: 10/Jun/21 07:44
• Resolved: 06/Mar/21 22:31

Description

To monitor how often read/write locks exceed thresholds, we can add two metrics(ReadLockLongHoldCount/WriteLockLongHoldCount), which are exposed in JMX.

Issue Links

• is related to: HDFS-15849 ExpiredHeartbeats metric should be of Type.COUNTER
• links to: GitHub Pull Request #2668