After digging into the code and test I think that the problem is almost certainly in the UnilateralSortMerger, there should be a missing synchronization on some shared object somewhere...Right now I'm trying to understand if this section of code creates some shared object (like queues) that are accessed in a bad way when there's spilling to disk:
// start the thread that reads the input channels this.readThread = getReadingThread(exceptionHandler, input, circularQueues, largeRecordHandler, parentTask, serializer, ((long) (startSpillingFraction * sortMemory))); // start the thread that sorts the buffers this.sortThread = getSortingThread(exceptionHandler, circularQueues, parentTask); // start the thread that handles spilling to secondary storage this.spillThread = getSpillingThread(exceptionHandler, circularQueues, parentTask, memoryManager, ioManager, serializerFactory, comparator, this.sortReadMemory, this.writeMemory, maxNumFileHandles); .... startThreads(); The problem is that the unit tests of GroupReduceDriver use Record and testing Rows in not very straightforward and I'm still trying to reproduce the problem in a local env.. On Fri, Apr 21, 2017 at 9:53 PM, Flavio Pompermaier <pomperma...@okkam.it> wrote: > Thanks for the explanation . Is there a way to force this behaviour in a > local environment (to try to debug the problem)? > > On 21 Apr 2017 21:49, "Fabian Hueske" <fhue...@gmail.com> wrote: > >> Hi Flavio, >> >> these files are used for spilling data to disk. In your case sorted runs >> of records. >> Later all (up to a fanout threshold) these sorted runs are read and >> merged to get a completely sorted record stream. >> >> 2017-04-21 14:09 GMT+02:00 Flavio Pompermaier <pomperma...@okkam.it>: >> >>> The error appears as soon as some taskmanager generates some >>> inputchannel file. >>> What are those files used for? >>> >>> On Fri, Apr 21, 2017 at 11:53 AM, Flavio Pompermaier < >>> pomperma...@okkam.it> wrote: >>> >>>> In another run of the job I had another Exception. Could it be helpful? >>>> >>>> Error obtaining the sorted input: Thread 'SortMerger Reading Thread' >>>> terminated due to an exception: Serializer consumed more bytes than the >>>> record had. This indicates broken serialization. If you are using custom >>>> serialization types (Value or Writable), check their serialization methods. >>>> If you are using a Kryo-serialized type, check the corresponding Kryo >>>> serializer. >>>> at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:465) >>>> at org.apache.flink.runtime.operators.BatchTask.invoke(BatchTas >>>> k.java:355) >>>> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:655) >>>> at java.lang.Thread.run(Thread.java:745) >>>> Caused by: java.lang.RuntimeException: Error obtaining the sorted >>>> input: Thread 'SortMerger Reading Thread' terminated due to an exception: >>>> Serializer consumed more bytes than the record had. This indicates broken >>>> serialization. If you are using custom serialization types (Value or >>>> Writable), check their serialization methods. If you are using a >>>> Kryo-serialized type, check the corresponding Kryo serializer. >>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>> .getIterator(UnilateralSortMerger.java:619) >>>> at org.apache.flink.runtime.operators.BatchTask.getInput(BatchT >>>> ask.java:1094) >>>> at org.apache.flink.runtime.operators.GroupReduceDriver.prepare >>>> (GroupReduceDriver.java:99) >>>> at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:460) >>>> ... 3 more >>>> Caused by: java.io.IOException: Thread 'SortMerger Reading Thread' >>>> terminated due to an exception: Serializer consumed more bytes than the >>>> record had. This indicates broken serialization. If you are using custom >>>> serialization types (Value or Writable), check their serialization methods. >>>> If you are using a Kryo-serialized type, check the corresponding Kryo >>>> serializer. >>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>> $ThreadBase.run(UnilateralSortMerger.java:799) >>>> Caused by: java.io.IOException: Serializer consumed more bytes than the >>>> record had. This indicates broken serialization. If you are using custom >>>> serialization types (Value or Writable), check their serialization methods. >>>> If you are using a Kryo-serialized type, check the corresponding Kryo >>>> serializer. >>>> at org.apache.flink.runtime.io.network.api.serialization.Spilli >>>> ngAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingA >>>> daptiveSpanningRecordDeserializer.java:123) >>>> at org.apache.flink.runtime.io.network.api.reader.AbstractRecor >>>> dReader.getNextRecord(AbstractRecordReader.java:72) >>>> at org.apache.flink.runtime.io.network.api.reader.MutableRecord >>>> Reader.next(MutableRecordReader.java:42) >>>> at org.apache.flink.runtime.operators.util.ReaderIterator.next( >>>> ReaderIterator.java:59) >>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>> $ReadingThread.go(UnilateralSortMerger.java:1035) >>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>> $ThreadBase.run(UnilateralSortMerger.java:796) >>>> Caused by: java.lang.ArrayIndexOutOfBoundsException: 32768 >>>> at org.apache.flink.core.memory.HeapMemorySegment.get(HeapMemor >>>> ySegment.java:104) >>>> at org.apache.flink.runtime.io.network.api.serialization.Spilli >>>> ngAdaptiveSpanningRecordDeserializer$NonSpanningWrapper.read >>>> Byte(SpillingAdaptiveSpanningRecordDeserializer.java:226) >>>> at org.apache.flink.runtime.io.network.api.serialization.Spilli >>>> ngAdaptiveSpanningRecordDeserializer$NonSpanningWrapper.read >>>> UnsignedByte(SpillingAdaptiveSpanningRecordDeserializer.java:231) >>>> at org.apache.flink.types.StringValue.readString(StringValue.java:770) >>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>> deserialize(StringSerializer.java:69) >>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>> deserialize(StringSerializer.java:74) >>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>> deserialize(StringSerializer.java:28) >>>> at org.apache.flink.api.java.typeutils.runtime.RowSerializer.de >>>> serialize(RowSerializer.java:193) >>>> at org.apache.flink.api.java.typeutils.runtime.RowSerializer.de >>>> serialize(RowSerializer.java:36) >>>> at org.apache.flink.runtime.plugable.ReusingDeserializationDele >>>> gate.read(ReusingDeserializationDelegate.java:57) >>>> at org.apache.flink.runtime.io.network.api.serialization.Spilli >>>> ngAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingA >>>> daptiveSpanningRecordDeserializer.java:109) >>>> ... 5 more >>>> >>>> On Fri, Apr 21, 2017 at 11:43 AM, Stefano Bortoli < >>>> stefano.bort...@huawei.com> wrote: >>>> >>>>> In fact the old problem was with the KryoSerializer missed >>>>> initialization on the exception that would trigger the spilling on disk. >>>>> This would lead to dirty serialization buffer that would eventually break >>>>> the program. Till worked on it debugging the source code generating the >>>>> error. Perhaps someone could try the same also this time. If Flavio can >>>>> make the problem reproducible in a shareable program+data. >>>>> >>>>> >>>>> >>>>> Stefano >>>>> >>>>> >>>>> >>>>> *From:* Stephan Ewen [mailto:se...@apache.org] >>>>> *Sent:* Friday, April 21, 2017 10:04 AM >>>>> *To:* user <user@flink.apache.org> >>>>> *Subject:* Re: UnilateralSortMerger error (again) >>>>> >>>>> >>>>> >>>>> In the past, these errors were most often caused by bugs in the >>>>> serializers, not in the sorter. >>>>> >>>>> >>>>> >>>>> What types are you using at that point? The Stack Trace reveals ROW >>>>> and StringValue, any other involved types? >>>>> >>>>> >>>>> >>>>> On Fri, Apr 21, 2017 at 9:36 AM, Flavio Pompermaier < >>>>> pomperma...@okkam.it> wrote: >>>>> >>>>> As suggested by Fabian I set taskmanager.memory.size = 1024 (to force >>>>> spilling to disk) and the job failed almost immediately.. >>>>> >>>>> >>>>> >>>>> On Fri, Apr 21, 2017 at 12:33 AM, Flavio Pompermaier < >>>>> pomperma...@okkam.it> wrote: >>>>> >>>>> I debugged a bit the process repeating the job on a sub-slice of the >>>>> entire data (using the id value to filter data with parquet push down >>>>> filters) and all slices completed successfully :( >>>>> >>>>> So I tried to increase the parallelism (from 1 slot per TM to 4) to >>>>> see if this was somehow a factor of stress but it didn't cause any error. >>>>> >>>>> Then I almost doubled the number of rows to process and finally the >>>>> error showed up again. >>>>> >>>>> It seems somehow related to spilling to disk but I can't really >>>>> understand what's going on :( >>>>> >>>>> This is a summary of my debug attempts: >>>>> >>>>> >>>>> >>>>> 4 Task managers with 6 GB and 1 slot each, parallelism = 4 >>>>> >>>>> >>>>> >>>>> id < 10.000.000.000 => 1.857.365 rows => OK >>>>> >>>>> id >= 10.000.000.000 && id < 10.010.000.000 => 20.057.714 rows => OK >>>>> >>>>> id >= 10.010.000.000 && id < 99.945.000.000 => 20.926.903 rows >>>>> => OK >>>>> >>>>> id >= 99.945.000.000 && id < 99.960.000.000 => 23.888.750 rows >>>>> => OK >>>>> >>>>> id >= 99.960.000.000 => 32.936.422 rows => OK >>>>> >>>>> >>>>> >>>>> 4 TM with 8 GB and 4 slot each, parallelism 16 >>>>> >>>>> >>>>> id >= 99.960.000.000 => 32.936.422 rows => OK >>>>> >>>>> id >= 99.945.000.000 => 56.825.172 rows => ERROR >>>>> >>>>> >>>>> >>>>> Any help is appreciated.. >>>>> >>>>> Best, >>>>> >>>>> Flavio >>>>> >>>>> >>>>> >>>>> On Wed, Apr 19, 2017 at 8:34 PM, Flavio Pompermaier < >>>>> pomperma...@okkam.it> wrote: >>>>> >>>>> I could but only if there's a good probability that it fix the >>>>> problem...how confident are you about it? >>>>> >>>>> >>>>> >>>>> On Wed, Apr 19, 2017 at 8:27 PM, Ted Yu <yuzhih...@gmail.com> wrote: >>>>> >>>>> Looking at git log of DataInputDeserializer.java , there has been some >>>>> recent change. >>>>> >>>>> >>>>> >>>>> If you have time, maybe try with 1.2.1 RC and see if the error is >>>>> reproducible ? >>>>> >>>>> >>>>> >>>>> Cheers >>>>> >>>>> >>>>> >>>>> On Wed, Apr 19, 2017 at 11:22 AM, Flavio Pompermaier < >>>>> pomperma...@okkam.it> wrote: >>>>> >>>>> Hi to all, >>>>> >>>>> I think I'm again on the weird Exception with the >>>>> SpillingAdaptiveSpanningRecordDeserializer... >>>>> >>>>> I'm using Flink 1.2.0 and the error seems to rise when Flink spills to >>>>> disk but the Exception thrown is not very helpful. Any idea? >>>>> >>>>> >>>>> >>>>> Caused by: java.lang.RuntimeException: Error obtaining the sorted >>>>> input: Thread 'SortMerger Reading Thread' terminated due to an exception: >>>>> null >>>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>>> .getIterator(UnilateralSortMerger.java:619) >>>>> at org.apache.flink.runtime.operators.BatchTask.getInput(BatchT >>>>> ask.java:1094) >>>>> at org.apache.flink.runtime.operators.GroupReduceDriver.prepare >>>>> (GroupReduceDriver.java:99) >>>>> at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.j >>>>> ava:460) >>>>> ... 3 more >>>>> Caused by: java.io.IOException: Thread 'SortMerger Reading Thread' >>>>> terminated due to an exception: null >>>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>>> $ThreadBase.run(UnilateralSortMerger.java:799) >>>>> Caused by: java.io.EOFException >>>>> at org.apache.flink.runtime.util.DataInputDeserializer.readUnsi >>>>> gnedByte(DataInputDeserializer.java:306) >>>>> at org.apache.flink.types.StringValue.readString(StringValue.java:747) >>>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>>> deserialize(StringSerializer.java:69) >>>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>>> deserialize(StringSerializer.java:74) >>>>> at org.apache.flink.api.common.typeutils.base.StringSerializer. >>>>> deserialize(StringSerializer.java:28) >>>>> at org.apache.flink.api.java.typeutils.runtime.RowSerializer.de >>>>> serialize(RowSerializer.java:193) >>>>> at org.apache.flink.api.java.typeutils.runtime.RowSerializer.de >>>>> serialize(RowSerializer.java:36) >>>>> at org.apache.flink.runtime.plugable.ReusingDeserializationDele >>>>> gate.read(ReusingDeserializationDelegate.java:57) >>>>> at org.apache.flink.runtime.io.network.api.serialization.Spilli >>>>> ngAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingA >>>>> daptiveSpanningRecordDeserializer.java:144) >>>>> at org.apache.flink.runtime.io.network.api.reader.AbstractRecor >>>>> dReader.getNextRecord(AbstractRecordReader.java:72) >>>>> at org.apache.flink.runtime.io.network.api.reader.MutableRecord >>>>> Reader.next(MutableRecordReader.java:42) >>>>> at org.apache.flink.runtime.operators.util.ReaderIterator.next( >>>>> ReaderIterator.java:59) >>>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>>> $ReadingThread.go(UnilateralSortMerger.java:1035) >>>>> at org.apache.flink.runtime.operators.sort.UnilateralSortMerger >>>>> $ThreadBase.run(UnilateralSortMerger.java:796) >>>>> >>>>> >>>>> Best, >>>>> >>>>> Flavio >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>> >>