Hi, I'm running a scala flink app in an AWS EMR cluster (emr 5.17, hadoop 2.8.4) with flink parallelization set to 400. The source is a Kafka topic and sinks to S3 in the format of: s3://<day>/<hour>/<worker_number>/<files>. There's potentially 400 files writing simultaneously.
Configuration:
- Flink v1.5.2
- Checkpointing enabled w/ RocksDb (flink-statebackend-rocksdb_2.11, v1.6.1). Interval is every 2 mins with max concurrent set to 1. Min pause between checkpoints in 2 mins. Timeout is set to 2 mins.
- BucketingSink (flink-connector-filesystem_2.11, v1.6.1).
- Batch file size is set to 5mb.
- Batch rollover interval is set to 30min
- Writer uses GZip compression
- Hadoop Maven Dependencies (hadoop-hdfs v3.1.1, hadoop-common v3.1.1, hadoop-core v1.2.1, hadoop-aws v3.1.1)
The app is able to run for hours straight, but occasionally (once or twice a day), it displays the following exception. When this happens, the app is able to recover from previous checkpoint, but I am concerned about the exception:
Caused by: java.io.IOException: com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.services.s3.model.AmazonS3Exception: Not Found (Service: Amazon S3; Status Code 404; Error ... Request ID: xxxxxxxx, S3 Extended Request ID: xxxxxxxxxxxxxxxxxxxxxxxxxx
- at com.amazon.ws.emr.hadoop.fs.s3n.Jets3tNativeFileSystemStore.handleAmazonServiceException(Jets3tNativeFileSystemStore.java:446)
- at com.amazon.ws.emr.hadoop.fs.s3n.Jets3tNativeFileSystemStore.copy(Jets3tNativeFileSystemStore.java:427)
- at com.amazon.ws.emr.hadoop.fs.s3n.S3NativeFileSystem.rename(S3NativeFileSystem.java:1297)
- at com.amazon.ws.emr.hadoop.fs.EmrFileSystem.rename(EmrFileSystem.java:312)
- at org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.handlePendingInProgressFile(BucketingSink.java:815)
Caused by: com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.services.s3.model.AmazonS3Exception: Not Found (Service: Amazon S3; Status Code 404; Error ... Request ID: xxxxxxxx, S3 Extended Request ID: xxxxxxxxxxxxxxxxxxxxxxxxxx
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.handleErrorResponse(AmazonHttpClient.java:1632)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeOneRequest(AmazonHttpClient.java:1304)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeHelper(AmazonHttpClient.java:1058)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.doExecute(AmazonHttpClient.java:743)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeWithTimer(AmazonHttpClient.java:717)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.execute(AmazonHttpClient.java:699)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutor.access$500(AmazonHttpClient.java:667)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient$RequestExecutionBuilderImpl.execute(AmazonHttpClient.java:649)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:513)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:4365)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:4312)
- at com.amazon.ws.emr.hadoop.fs.shaded.com.amazonaws.services.s3.AmazonS3Client.getObjectMetadata(AmazonS3Client.java:1270)
- at com.amazon.ws.emr.hadoop.fs.s3.lite.call.GetObjectMetadataCall.perform(GetObjectMetadataCall.java:22)
- at com.amazon.ws.emr.hadoop.fs.s3.lite.call.GetObjectMetadataCall.perform(GetObjectMetadataCall.java:8)
- at com.amazon.ws.emr.hadoop.fs.s3.lite.executor.GlobalS3Exxecutor.execute(GlobalS3Executor.java:91)
And sometimes, it will show this:
- java.lang.RuntimeException: Error while restoring BucketingSink state.
- at org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.handlePendingInProgressFile(BucketingSink.java:888)
- at org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.handleRestoredBucketState(BucketingSink.java:767)
- at org.apache.flink.streaming.connectors.fs.bucketing.BucketingSink.initializeState(BucketingSink.java:394)
- at org.apache.flink.streaming.util.functions.StreamingFunctionUtils.tryRestoreFunction(StreamingFunctionUtils.java:178)
- at org.apache.flink.streaming.util.functions.StreamingFunctionUtils.restoreFunctionState(StreamingFunctionUtils.java:160)
- at org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.initializeState(AbstractUdfStreamOperator.java:96)
- at org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:254)
- at org.apache.flink.streaming.runtime.tasks.StreamTask.initializeState(StreamTask.java:730)
- at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:295)
- at org.apache.flink.runtime.taskmanager.Task.run(Task.java:703)
What causes this and how can it be resolved? Thank you.
There seems to be a related Flink ticket and PR here, but I'm not sure if this is the exact same issue and if it has been resolved: