[HDFS-723] Deadlock in DFSClient#DFSOutputStream

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 0.20.2
• Hadoop Flags: Reviewed
• Assignee: Hairong Kuang
• Reporter: Hairong Kuang
• Created: 21/Oct/09 20:50
• Updated: 27/Oct/09 13:29
• Resolved: 26/Oct/09 21:44

Description

WhiIe was running some append-related tests, I hit this deadlock:

Found one Java-level deadlock:
=============================
"Thread-3":
  waiting to lock monitor 0x000000012ee044f0 (object 0x0000000107a0ded0, a org.apache.hadoop.hdfs.DFSClient$DFSOutputStream),
  which is held by "main"
"main":
  waiting to lock monitor 0x000000012eeb71a8 (object 0x00000001082b0748, a org.apache.hadoop.hdfs.DFSClient$LeaseChecker),
  which is held by "Thread-3"

Java stack information for the threads listed above:
===================================================
"Thread-3":
	at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.close(DFSClient.java:3582)
	- waiting to lock <0x0000000107a0ded0> (a org.apache.hadoop.hdfs.DFSClient$DFSOutputStream)
	at org.apache.hadoop.hdfs.DFSClient$LeaseChecker.close(DFSClient.java:1175)
	- locked <0x00000001082b0748> (a org.apache.hadoop.hdfs.DFSClient$LeaseChecker)
	at org.apache.hadoop.hdfs.DFSClient.close(DFSClient.java:306)
	- locked <0x000000010824d640> (a org.apache.hadoop.hdfs.DFSClient)
        - waiting to lock <0x0000000107a0ded0> (a org.apache.hadoop.hdfs.DFSClient$DFSOutputStream)
        at org.apache.hadoop.hdfs.DFSClient$LeaseChecker.close(DFSClient.java:1175)
        - locked <0x00000001082b0748> (a org.apache.hadoop.hdfs.DFSClient$LeaseChecker)
        at org.apache.hadoop.hdfs.DFSClient.close(DFSClient.java:306)
        - locked <0x000000010824d640> (a org.apache.hadoop.hdfs.DFSClient)
        at org.apache.hadoop.hdfs.DistributedFileSystem.close(DistributedFileSystem.java:325)
        at org.apache.hadoop.fs.FileSystem$Cache.closeAll(FileSystem.java:1835)
        - locked <0x0000000107a77ec8> (a org.apache.hadoop.fs.FileSystem$Cache)
        at org.apache.hadoop.fs.FileSystem$Cache$ClientFinalizer.run(FileSystem.java:1851)
        - locked <0x00000001079daa00> (a org.apache.hadoop.fs.FileSystem$Cache$ClientFinalizer)
"main":
        at org.apache.hadoop.hdfs.DFSClient$LeaseChecker.remove(DFSClient.java:1151)
        - waiting to lock <0x00000001082b0748> (a org.apache.hadoop.hdfs.DFSClient$LeaseChecker)
        at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.close(DFSClient.java:3609)
        - locked <0x0000000107a0ded0> (a org.apache.hadoop.hdfs.DFSClient$DFSOutputStream)
        at org.apache.hadoop.fs.FSDataOutputStream$PositionCache.close(FSDataOutputStream.java:61)
        at org.apache.hadoop.fs.FSDataOutputStream.close(FSDataOutputStream.java:86)
        at org.apache.hadoop.hdfs.TestFileAppend4.testAppend(TestFileAppend4.java:99)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at junit.framework.TestCase.runTest(TestCase.java:168)
        at junit.framework.TestCase.runBare(TestCase.java:134)
        at junit.framework.TestResult$1.protect(TestResult.java:110)
        at junit.framework.TestResult.runProtected(TestResult.java:128)
        at junit.framework.TestResult.run(TestResult.java:113)
        at junit.framework.TestCase.run(TestCase.java:124)
        at junit.framework.TestSuite.runTest(TestSuite.java:232)
        at junit.framework.TestSuite.run(TestSuite.java:227)
        at junit.extensions.TestDecorator.basicRun(TestDecorator.java:24)
        at junit.extensions.TestSetup$1.protect(TestSetup.java:23)
        at junit.framework.TestResult.runProtected(TestResult.java:128)
        at junit.extensions.TestSetup.run(TestSetup.java:27)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:420)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:911)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:768)