Description
Whenever FsNameSystemLock is held for more than configured value of dfs.namenode.write-lock-reporting-threshold-ms, we log stacktrace and an entry in metrics. Loading FSImage from disk will usually cross this threshold. We can suppress this FsNamesystem lock warning on NameNode startup.
17/09/20 21:41:39 INFO namenode.FSNamesystem: FSNamesystem write lock held for 7159 ms via java.lang.Thread.getStackTrace(Thread.java:1552) org.apache.hadoop.util.StringUtils.getStackTrace(StringUtils.java:945) org.apache.hadoop.hdfs.server.namenode.FSNamesystem.writeUnlock(FSNamesystem.java:1659) org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFSImage(FSNamesystem.java:1074) org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFromDisk(FSNamesystem.java:703) org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:688) org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:752) org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:992) org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:976) org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1701) org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1769) Number of suppressed write-lock reports: 0 Longest write-lock held interval: 7159