You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@flink.apache.org by "Matthias (Jira)" <ji...@apache.org> on 2021/09/03 09:54:00 UTC
[jira] [Commented] (FLINK-24147) HDFS lease issues on Flink retry
[ https://issues.apache.org/jira/browse/FLINK-24147?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17409408#comment-17409408 ]
Matthias commented on FLINK-24147:
----------------------------------
[~twalthr] does the reasoning make sense here or did we misinterpret the fixed retry suffix {{_0}} in the code? I still have doubts because I would have assumed this issue would pop up more frequently if there's really a race condition between a too low retry interval on the Flink side and the soft limit for leases of 1min on the HDFS side.
> HDFS lease issues on Flink retry
> --------------------------------
>
> Key: FLINK-24147
> URL: https://issues.apache.org/jira/browse/FLINK-24147
> Project: Flink
> Issue Type: Bug
> Components: Connectors / Hadoop Compatibility
> Affects Versions: 1.14.0, 1.12.5, 1.13.2
> Reporter: Matthias
> Priority: Major
> Attachments: jobmanager.log
>
>
> This issue was brought up on the [ML thread "hdfs lease issues on flink retry"|https://lists.apache.org/x/thread.html/r9e5dc9cbd0a41b88565bd6c8c1c9d864ffdd343b4a96bd4dd0dd8a97@%3Cuser.flink.apache.org%3E]. See attached [^jobmanager.log] which was provided by the user:
> {code}
> org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException): Failed to CREATE_FILE /user/p2epda/lake/delp_prod/PROD/APPROVED/data/gsam_qa_campaign_extract/NmsRtEvent/2728/temp/data/_temporary/0/_temporary/attempt__0000_r_000008_0/partMapper-r-00008.snappy.parquet for DFSClient_NONMAPREDUCE_-910267331_98 on 10.59.155.152 because this file lease is currently owned by DFSClient_NONMAPREDUCE_1747340094_77 on 10.50.196.245
> at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.recoverLeaseInternal(FSNamesystem.java:3194)
> at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:2813)
> at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInt(FSNamesystem.java:2702)
> at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFile(FSNamesystem.java:2586)
> at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.create(NameNodeRpcServer.java:736)
> at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.create(ClientNamenodeProtocolServerSideTranslatorPB.java:409)
> at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
> at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:640)
> at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:982)
> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2351)
> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2347)
> at java.security.AccessController.doPrivileged(Native Method)
> at javax.security.auth.Subject.doAs(Subject.java:422)
> at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1899)
> at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2347)
> at org.apache.hadoop.ipc.Client.getRpcResponse(Client.java:1554)
> at org.apache.hadoop.ipc.Client.call(Client.java:1498)
> at org.apache.hadoop.ipc.Client.call(Client.java:1398)
> at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:233)
> at com.sun.proxy.$Proxy19.create(Unknown Source)
> at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.create(ClientNamenodeProtocolTranslatorPB.java:313)
> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
> at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> at java.lang.reflect.Method.invoke(Method.java:498)
> at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:290)
> at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:202)
> at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:184)
> at com.sun.proxy.$Proxy20.create(Unknown Source)
> at org.apache.hadoop.hdfs.DFSOutputStream.newStreamForCreate(DFSOutputStream.java:1828)
> at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1712)
> at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1647)
> at org.apache.hadoop.hdfs.DistributedFileSystem$8.doCall(DistributedFileSystem.java:480)
> at org.apache.hadoop.hdfs.DistributedFileSystem$8.doCall(DistributedFileSystem.java:476)
> at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
> at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:491)
> at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:417)
> at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:930)
> at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:911)
> at org.apache.parquet.hadoop.ParquetFileWriter.<init>(ParquetFileWriter.java:236)
> at org.apache.parquet.hadoop.ParquetOutputFormat.getRecordWriter(ParquetOutputFormat.java:342)
> at org.apache.parquet.hadoop.ParquetOutputFormat.getRecordWriter(ParquetOutputFormat.java:302)
> at com.gs.ep.lake.flinkbasics.GRHadoopOutputFormat.open(GRHadoopOutputFormat.java:90)
> at org.apache.flink.runtime.operators.DataSinkTask.invoke(DataSinkTask.java:205)
> at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:705)
> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:530)
> at java.lang.Thread.run(Thread.java:745)
> {code}
> The user ran into {{FileAlreadyExistsException}} when it tried to create a file for which a lease already existed. Admittedly, they use their own implementation with {{GRHadoopOutputFormat}}. But [~dmvk] helped investigating this as he was familiar with the error.
> We seem to have the problem in {{HadoopOutputFormatBase}} where we use a fixed retry id {{0}} in [HadoopOutputFormatBase:137|https://github.com/apache/flink/blob/c6997c97c575d334679915c328792b8a3067cfb5/flink-connectors/flink-hadoop-compatibility/src/main/java/org/apache/flink/api/java/hadoop/mapred/HadoopOutputFormatBase.java#L137].
> Each resource in HDFS is allowed to have only one Writer accessing it. The LeaseManager manages this through leases. It appears that we tried to access the same file through another task due to {{HadoopOutputFormatBase}} generating the same {{TaskAttemptId}}. The retry interval was shorter (in that case 10 seconds) than Hadoop's hard-coded soft lease limit of 1min (see [hadoop:HdfsConstants:62|https://github.com/apache/hadoop/blob/a9c1489e31e8f602de62bd3ecc517aa6597ab2f8/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/HdfsConstants.java#L62]).
> We could be able to overcome this by adding a dynamic retry count instead of {{_0}}.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)