版本: hadoop cdh5.4 datanode jstack，很多这样的线程
"DataXceiver for client unix:/var/run/hdfs-sockets/dn [Waiting for operation #1]" daemon prio=10 tid=0x00007ffc42de9000 nid=0x68f8 waiting on condition [0x00007ffacbd1d000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000007a5d3d568> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
at org.apache.hadoop.net.unix.DomainSocketWatcher.add(DomainSocketWatcher.java:316)
at org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry.createNewMemorySegment(ShortCircuitRegistry.java:322)
at org.apache.hadoop.hdfs.server.datanode.DataXceiver.requestShortCircuitShm(DataXceiver.java:418)
at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.opRequestShortCircuitShm(Receiver.java:214)
at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.processOp(Receiver.java:95)
at org.apache.hadoop.hdfs.server.datanode.DataXceiver.run(DataXceiver.java:241)
at java.lang.Thread.run(Thread.java:745)
相关issue
[HADOOP-11333] – Fix deadlock in DomainSocketWatcher when the notification pipe is full
[HADOOP-10404] – Some accesses to DomainSocketWatcher#closed are not protected by lock
https://issues.apache.org/jira/browse/HADOOP-11604
https://issues.apache.org/jira/browse/HADOOP-11802
https://issues.apache.org/jira/browse/HDFS-8429