[HDFS-15217] Add more information to longest write/read lock held log

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.4.0
• Fix Version/s: 3.4.0
• Component/s: namenode
• Target Version/s: 3.4.0
• Hadoop Flags: Reviewed
• Assignee: Toshihiro Suzuki
• Reporter: Toshihiro Suzuki
• Created: 10/Mar/20 12:58
• Updated: 16/Oct/24 18:29
• Resolved: 18/Apr/20 20:52

Description

Currently, we can see the stack trace in the longest write/read lock held log, but sometimes we need more information, for example, a target path of deletion:

2020-03-10 21:51:21,116 [main] INFO  namenode.FSNamesystem (FSNamesystemLock.java:writeUnlock(276)) - 	Number of suppressed write-lock reports: 0
	Longest write-lock held at 2020-03-10 21:51:21,107+0900 for 6ms via java.lang.Thread.getStackTrace(Thread.java:1559)
org.apache.hadoop.util.StringUtils.getStackTrace(StringUtils.java:1058)
org.apache.hadoop.hdfs.server.namenode.FSNamesystemLock.writeUnlock(FSNamesystemLock.java:257)
org.apache.hadoop.hdfs.server.namenode.FSNamesystemLock.writeUnlock(FSNamesystemLock.java:233)
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.writeUnlock(FSNamesystem.java:1706)
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.delete(FSNamesystem.java:3188)
...

Adding more information (opName, path, etc.) to the log is useful to troubleshoot.

Issue Links

• breaks: HDFS-15298 Fix the findbugs warnings introduced in HDFS-15217
• is related to: HDFS-14775 Add Timestamp for longest FSN write/read lock held log
• relates to: HDFS-15718 Optimize hdfs token op writeLock
• links to: GitHub Pull Request #1954