[MAPREDUCE-6905] Fix meaningless operations in TestDFSIO in some situation.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.0-alpha4
• Fix Version/s: 2.9.0, 3.0.0-beta1, 2.8.2
• Component/s: tools/rumen
• Labels: patch
• Target Version/s: 3.0.0-beta1
• Hadoop Flags: Reviewed
• Flags: Patch
• Assignee: LiXin Ge
• Reporter: LiXin Ge
• Created: 26/Jun/17 08:18
• Updated: 28/Aug/17 18:35
• Resolved: 02/Jul/17 11:08

Description

When run TestDFSIO in write mode with 2 million nrFiles, it will takes hours to create control files and get IOException as last because of directory item limit is exceeded. And, it will leave over 1 million useless files which will be deleted when run TestDFSIO again with acceptable nrFiles.

17/06/21 09:12:16 INFO fs.TestDFSIO: creating control file: 1024 bytes, 2000000 files
java.io.IOException: The directory item limit of /benchmarks/TestDFSIO/io_control is exceeded: limit=1048576 items=1048576
at org.apache.hadoop.hdfs.server.namenode.FSDirectory.verifyMaxDirItems(FSDirectory.java:2033)
at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addChild(FSDirectory.java:2084)
at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addLastINode(FSDirectory.java:2053)
at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addINode(FSDirectory.java:1873)
at org.apache.hadoop.hdfs.server.namenode.FSDirectory.addFile(FSDirectory.java:327)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:2750)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInt(FSNamesystem.java:2632)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFile(FSNamesystem.java:2520)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.create(NameNodeRpcServer.java:579)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.create(ClientNamenodeProtocolServerSideTranslatorPB.java:394)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:619)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:962)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2040)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2036)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1656)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2034)
at org.apache.hadoop.fs.TestDFSIO.createControlFile(TestDFSIO.java:302)
at org.apache.hadoop.fs.TestDFSIO.run(TestDFSIO.java:751)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
at org.apache.hadoop.fs.TestDFSIO.main(TestDFSIO.java:650)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71)
at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
at org.apache.hadoop.test.MapredTestDriver.run(MapredTestDriver.java:118)
at org.apache.hadoop.test.MapredTestDriver.main(MapredTestDriver.java:126)

In brief, we'd better check the parameter of nrFiles before it waste our time and hurt our feelings.