私は、分析に必要な特定の要素をカウントする特定の時間範囲でhbaseテーブルをスキャンするmapreduceジョブを作成しました。複数の再試行後にマップジョブが失敗する理由をデバッグする方法
MRジョブのマッパーは失敗し続けますが、理由はわかりません。私が仕事をするたびに違う数のマッパが失敗するようです。 ClouderaのマネージャーのYARNログ（下記参照）は、問題が何であるかを指摘するのには役立たないが、誰かが私に記憶がなくなっているかもしれないと言った。
複数回再試行したようですが、失敗するたびに再試行されます。それが失敗するのを止めるために何をする必要がありますか、何が起きているのかをより良く判断するために、どのようにログを記録できますか？
以下は、失敗したマッパーの1つに対するYARNからのログです。
Error: org.apache.hadoop.hbase.client.RetriesExhaustedException: Failed after attempts=36, exceptions: Thu Jun 15 16:26:57 PDT 2017, null, java.net.SocketTimeoutException: callTimeout=60000, callDuration=60301: row '152_p3401.db161139.sjc102.dbi_1496271480' on table 'dbi_based_data' at region=dbi_based_data,151_p3413.db162024.iad4.dbi_1476974340,1486675565213.d83250d0682e648d165872afe5abd60e., hostname=hslave35118.ams9.mysecretdomain.com,60020,1483570489305, seqNum=19308931 at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.throwEnrichedException(RpcRetryingCallerWithReadReplicas.java:276) at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:207) at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:60) at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200) at org.apache.hadoop.hbase.client.ClientScanner.call(ClientScanner.java:320) at org.apache.hadoop.hbase.client.ClientScanner.loadCache(ClientScanner.java:403) at org.apache.hadoop.hbase.client.ClientScanner.next(ClientScanner.java:364) at org.apache.hadoop.hbase.mapreduce.TableRecordReaderImpl.nextKeyValue(TableRecordReaderImpl.java:236) at org.apache.hadoop.hbase.mapreduce.TableRecordReader.nextKeyValue(TableRecordReader.java:147) at org.apache.hadoop.hbase.mapreduce.TableInputFormatBase$1.nextKeyValue(TableInputFormatBase.java:216) at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.nextKeyValue(MapTask.java:556) at org.apache.hadoop.mapreduce.task.MapContextImpl.nextKeyValue(MapContextImpl.java:80) at org.apache.hadoop.mapreduce.lib.map.WrappedMapper$Context.nextKeyValue(WrappedMapper.java:91) at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144) at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341) at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:415) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1693) at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158) Caused by: java.net.SocketTimeoutException: callTimeout=60000, callDuration=60301: row '152_p3401.db161139.sjc102.dbi_1496271480' on table 'dbi_based_data' at region=dbi_based_data,151_p3413.db162024.iad4.dbi_1476974340,1486675565213.d83250d0682e648d165872afe5abd60e., hostname=hslave35118.ams9.mysecretdomain.com,60020,1483570489305, seqNum=19308931 at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithRetries(RpcRetryingCaller.java:159) at org.apache.hadoop.hbase.client.ResultBoundedCompletionService$QueueingFuture.run(ResultBoundedCompletionService.java:65) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) Caused by: java.io.IOException: Call to hslave35118.ams9.mysecretdomain.com/10.216.35.118:60020 failed on local exception: org.apache.hadoop.hbase.ipc.CallTimeoutException: Call id=12, waitTime=60001, operationTimeout=60000 expired. at org.apache.hadoop.hbase.ipc.AbstractRpcClient.wrapException(AbstractRpcClient.java:291) at org.apache.hadoop.hbase.ipc.RpcClientImpl.call(RpcClientImpl.java:1272) at org.apache.hadoop.hbase.ipc.AbstractRpcClient.callBlockingMethod(AbstractRpcClient.java:226) at org.apache.hadoop.hbase.ipc.AbstractRpcClient$BlockingRpcChannelImplementation.callBlockingMethod(AbstractRpcClient.java:331) at org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$BlockingStub.scan(ClientProtos.java:34094) at org.apache.hadoop.hbase.client.ScannerCallable.call(ScannerCallable.java:219) at org.apache.hadoop.hbase.client.ScannerCallable.call(ScannerCallable.java:64) at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200) at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas$RetryingRPC.call(ScannerCallableWithReplicas.java:360) at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas$RetryingRPC.call(ScannerCallableWithReplicas.java:334) at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithRetries(RpcRetryingCaller.java:126) ... 4 more Caused by: org.apache.hadoop.hbase.ipc.CallTimeoutException: Call id=12, waitTime=60001, operationTimeout=60000 expired. at org.apache.hadoop.hbase.ipc.Call.checkAndSetTimeout(Call.java:73) at org.apache.hadoop.hbase.ipc.RpcClientImpl.call(RpcClientImpl.java:1246) ... 13 more