Could this be caused by the disabled reference tracking in our Kryo
serializer? From the stack trace it looks like its failing when trying to
deserialize the traits that are wrapped in Options.
On Tue, 26 Apr 2016 at 10:09 Ufuk Celebi <u...@apache.org> wrote:
> Hey Timur,
>
> I'm sorry about this bad experience.
>
> From what I can tell, there is nothing unusual with your code. It's
> probably an issue with Flink.
>
> I think we have to wait a little longer to hear what others in the
> community say about this.
>
> @Aljoscha, Till, Robert: any ideas what might cause this?
>
> – Ufuk
>
>
> On Mon, Apr 25, 2016 at 6:50 PM, Timur Fayruzov
> <timur.fairu...@gmail.com> wrote:
> > Still trying to resolve this serialization issue. I was able to hack it
> by
> > 'serializing' `Record` to String and then 'deserializing' it in coGroup,
> but
> > boy its so ugly.
> >
> > So the bug is that it can't deserialize the case class that has the
> > structure (slightly different and more detailed than I stated above):
> > ```
> > case class Record(name: Name, phone: Option[Phone], address:
> > Option[Address])
> >
> > case class Name(givenName: Option[String], middleName: Option[String],
> > familyName: Option[String], generationSuffix: Option[String] = None)
> >
> > trait Address{
> > val city: String
> > val state: String
> > val country: String
> > val latitude: Double
> > val longitude: Double
> > val postalCode: String
> > val zip4: String
> > val digest: String
> > }
> >
> >
> > case class PoBox(city: String,
> > state: String,
> > country: String,
> > latitude: Double,
> > longitude: Double,
> > postalCode: String,
> > zip4: String,
> > digest: String,
> > poBox: String
> > ) extends Address
> >
> > case class PostalAddress(city: String,
> > state: String,
> > country: String,
> > latitude: Double,
> > longitude: Double,
> > postalCode: String,
> > zip4: String,
> > digest: String,
> > preDir: String,
> > streetName: String,
> > streetType: String,
> > postDir: String,
> > house: String,
> > aptType: String,
> > aptNumber: String
> > ) extends Address
> > ```
> >
> > I would expect that serialization is one of Flink cornerstones and
> should be
> > well tested, so there is a high chance of me doing things wrongly, but I
> > can't really find anything unusual in my code.
> >
> > Any suggestion what to try is highly welcomed.
> >
> > Thanks,
> > Timur
> >
> >
> > On Sun, Apr 24, 2016 at 3:26 AM, Timur Fayruzov <
> timur.fairu...@gmail.com>
> > wrote:
> >>
> >> Hello Robert,
> >>
> >> I'm on 1.0.0 compiled with Scala 2.11. The second exception was an issue
> >> with a cluster (that I didn't dig into), when I restarted the cluster I
> was
> >> able to go past it, so now I have the following exception:
> >>
> >> java.lang.Exception: The data preparation for task 'CHAIN CoGroup
> (CoGroup
> >> at
> >>
> com.whitepages.data.flink.FaithResolution$.pipeline(FaithResolution.scala:158))
> >> -> Filter (Filter at
> >>
> com.whitepages.data.flink.FaithResolution$.pipeline(FaithResolution.scala:159))'
> >> , caused an error: 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:455)
> >> at
> org.apache.flink.runtime.operators.BatchTask.invoke(BatchTask.java:345)
> >> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:559)
> >> 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(BatchTask.java:1079)
> >> at
> >>
> org.apache.flink.runtime.operators.CoGroupDriver.prepare(CoGroupDriver.java:97)
> >> at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:450)
> >> ... 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$ThreadBase.run(UnilateralSortMerger.java:799)
> >> Caused by: java.io.IOException: Serializer consumed more bytes than the
> >> record had. This indicates broken serialization. If you are using custom
> >> serialization types (Value or Writable), check their serialization
> methods.
> >> If you are using a Kryo-serialized type, check the corresponding Kryo
> >> serializer.
> >> at
> >> org.apache.flink.runtime.io
> .network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingAdaptiveSpanningRecordDeserializer.java:142)
> >> at
> >> org.apache.flink.runtime.io
> .network.api.reader.AbstractRecordReader.getNextRecord(AbstractRecordReader.java:65)
> >> at
> >> org.apache.flink.runtime.io
> .network.api.reader.MutableRecordReader.next(MutableRecordReader.java:34)
> >> at
> >>
> org.apache.flink.runtime.operators.util.ReaderIterator.next(ReaderIterator.java:59)
> >> at
> >>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger$ReadingThread.go(UnilateralSortMerger.java:1035)
> >> at
> >>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger$ThreadBase.run(UnilateralSortMerger.java:796)
> >> Caused by: java.lang.ArrayIndexOutOfBoundsException: 32768
> >> at
> >>
> org.apache.flink.core.memory.HeapMemorySegment.get(HeapMemorySegment.java:104)
> >> at
> >> org.apache.flink.runtime.io
> .network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer$NonSpanningWrapper.readByte(SpillingAdaptiveSpanningRecordDeserializer.java:254)
> >> at
> >> org.apache.flink.runtime.io
> .network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer$NonSpanningWrapper.readUnsignedByte(SpillingAdaptiveSpanningRecordDeserializer.java:259)
> >> at org.apache.flink.types.StringValue.readString(StringValue.java:771)
> >> 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.TupleSerializer.deserialize(TupleSerializer.java:144)
> >> at
> >>
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.deserialize(TupleSerializer.java:30)
> >> at
> >>
> org.apache.flink.runtime.plugable.ReusingDeserializationDelegate.read(ReusingDeserializationDelegate.java:57)
> >> at
> >> org.apache.flink.runtime.io
> .network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingAdaptiveSpanningRecordDeserializer.java:124)
> >> ... 5 more
> >>
> >> Thanks,
> >> Timur
> >>
> >> On Sun, Apr 24, 2016 at 2:45 AM, Robert Metzger <rmetz...@apache.org>
> >> wrote:
> >>>
> >>> For the second exception, can you check the logs of the failing
> >>> taskmanager (10.105.200.137)?
> >>> I guess these logs some details on why the TM timed out.
> >>>
> >>>
> >>> Are you on 1.0.x or on 1.1-SNAPSHOT?
> >>> We recently changed something related to the ExecutionConfig which has
> >>> lead to Kryo issues in the past.
> >>>
> >>>
> >>> On Sun, Apr 24, 2016 at 11:38 AM, Timur Fayruzov
> >>> <timur.fairu...@gmail.com> wrote:
> >>>>
> >>>> Trying to use ProtobufSerializer -- program consistently fails with
> the
> >>>> following exception:
> >>>>
> >>>> java.lang.IllegalStateException: Update task on instance
> >>>> 52b9d8ffa1c0bb7251a9731c565460eb @ ip-10-105-200-137 - 1 slots - URL:
> >>>> akka.tcp://flink@10.105.200.137:48990/user/taskmanager failed due to:
> >>>> at
> >>>>
> org.apache.flink.runtime.executiongraph.Execution$6.onFailure(Execution.java:954)
> >>>> at akka.dispatch.OnFailure.internal(Future.scala:228)
> >>>> at akka.dispatch.OnFailure.internal(Future.scala:227)
> >>>> at akka.dispatch.japi$CallbackBridge.apply(Future.scala:174)
> >>>> at akka.dispatch.japi$CallbackBridge.apply(Future.scala:171)
> >>>> at scala.PartialFunction$class.applyOrElse(PartialFunction.scala:123)
> >>>> at
> >>>>
> scala.runtime.AbstractPartialFunction.applyOrElse(AbstractPartialFunction.scala:28)
> >>>> at
> scala.concurrent.Future$$anonfun$onFailure$1.apply(Future.scala:136)
> >>>> at
> scala.concurrent.Future$$anonfun$onFailure$1.apply(Future.scala:134)
> >>>> at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32)
> >>>> at
> >>>>
> scala.concurrent.impl.ExecutionContextImpl$AdaptedForkJoinTask.exec(ExecutionContextImpl.scala:121)
> >>>> at
> scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
> >>>> at
> >>>>
> scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
> >>>> at
> >>>>
> scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
> >>>> at
> >>>>
> scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
> >>>> Caused by: akka.pattern.AskTimeoutException: Ask timed out on
> >>>> [Actor[akka.tcp://
> flink@10.105.200.137:48990/user/taskmanager#1418296501]]
> >>>> after [10000 ms]
> >>>> at
> >>>>
> akka.pattern.PromiseActorRef$$anonfun$1.apply$mcV$sp(AskSupport.scala:333)
> >>>> at akka.actor.Scheduler$$anon$7.run(Scheduler.scala:117)
> >>>> at
> >>>>
> scala.concurrent.Future$InternalCallbackExecutor$.unbatchedExecute(Future.scala:599)
> >>>> at
> >>>>
> scala.concurrent.BatchingExecutor$class.execute(BatchingExecutor.scala:109)
> >>>> at
> >>>>
> scala.concurrent.Future$InternalCallbackExecutor$.execute(Future.scala:597)
> >>>> at
> >>>>
> akka.actor.LightArrayRevolverScheduler$TaskHolder.executeTask(Scheduler.scala:467)
> >>>> at
> >>>>
> akka.actor.LightArrayRevolverScheduler$$anon$8.executeBucket$1(Scheduler.scala:419)
> >>>> at
> >>>>
> akka.actor.LightArrayRevolverScheduler$$anon$8.nextTick(Scheduler.scala:423)
> >>>> at
> >>>>
> akka.actor.LightArrayRevolverScheduler$$anon$8.run(Scheduler.scala:375)
> >>>> at java.lang.Thread.run(Thread.java:745)
> >>>>
> >>>> I'm at my wits' end now, any suggestions are highly appreciated.
> >>>>
> >>>> Thanks,
> >>>> Timur
> >>>>
> >>>>
> >>>> On Sun, Apr 24, 2016 at 2:26 AM, Timur Fayruzov
> >>>> <timur.fairu...@gmail.com> wrote:
> >>>>>
> >>>>> Hello,
> >>>>>
> >>>>> I'm running a Flink program that is failing with the following
> >>>>> exception:
> >>>>>
> >>>>> 2016-04-23 02:00:38,947 ERROR org.apache.flink.client.CliFrontend
> >>>>> - Error while running the command.
> >>>>> org.apache.flink.client.program.ProgramInvocationException: The
> program
> >>>>> execution failed: Job execution failed.
> >>>>> at
> org.apache.flink.client.program.Client.runBlocking(Client.java:381)
> >>>>> at
> org.apache.flink.client.program.Client.runBlocking(Client.java:355)
> >>>>> at
> org.apache.flink.client.program.Client.runBlocking(Client.java:315)
> >>>>> at
> >>>>>
> org.apache.flink.client.program.ContextEnvironment.execute(ContextEnvironment.java:60)
> >>>>> at
> >>>>>
> org.apache.flink.api.java.ExecutionEnvironment.execute(ExecutionEnvironment.java:855)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.ExecutionEnvironment.execute(ExecutionEnvironment.scala:638)
> >>>>> at
> >>>>>
> com.whitepages.data.flink.FaithResolution$.pipeline(FaithResolution.scala:136)
> >>>>> at
> >>>>>
> com.whitepages.data.flink.FaithResolution$$anonfun$main$1.apply(FaithResolution.scala:48)
> >>>>> at
> >>>>>
> com.whitepages.data.flink.FaithResolution$$anonfun$main$1.apply(FaithResolution.scala:48)
> >>>>> at scala.Option.foreach(Option.scala:257)
> >>>>> at
> >>>>>
> com.whitepages.data.flink.FaithResolution$.main(FaithResolution.scala:48)
> >>>>> at
> >>>>> com.whitepages.data.flink.FaithResolution.main(FaithResolution.scala)
> >>>>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> >>>>> at
> >>>>>
> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
> >>>>> at
> >>>>>
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> >>>>> at java.lang.reflect.Method.invoke(Method.java:606)
> >>>>> at
> >>>>>
> org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:505)
> >>>>> at
> >>>>>
> org.apache.flink.client.program.PackagedProgram.invokeInteractiveModeForExecution(PackagedProgram.java:403)
> >>>>> at
> org.apache.flink.client.program.Client.runBlocking(Client.java:248)
> >>>>> at
> >>>>>
> org.apache.flink.client.CliFrontend.executeProgramBlocking(CliFrontend.java:866)
> >>>>> at org.apache.flink.client.CliFrontend.run(CliFrontend.java:333)
> >>>>> at
> >>>>>
> org.apache.flink.client.CliFrontend.parseParameters(CliFrontend.java:1189)
> >>>>> at org.apache.flink.client.CliFrontend.main(CliFrontend.java:1239)
> >>>>> Caused by: org.apache.flink.runtime.client.JobExecutionException: Job
> >>>>> execution failed.
> >>>>> at
> >>>>>
> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$7.apply$mcV$sp(JobManager.scala:714)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$7.apply(JobManager.scala:660)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$7.apply(JobManager.scala:660)
> >>>>> at
> >>>>>
> scala.concurrent.impl.Future$PromiseCompletingRunnable.liftedTree1$1(Future.scala:24)
> >>>>> at
> >>>>>
> scala.concurrent.impl.Future$PromiseCompletingRunnable.run(Future.scala:24)
> >>>>> at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:41)
> >>>>> at
> >>>>>
> akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:401)
> >>>>> at
> scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
> >>>>> at
> >>>>>
> scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.pollAndExecAll(ForkJoinPool.java:1253)
> >>>>> at
> >>>>>
> scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1346)
> >>>>> at
> >>>>>
> scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
> >>>>> at
> >>>>>
> scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
> >>>>> Caused by: java.lang.Exception: The data preparation for task 'CHAIN
> >>>>> CoGroup (CoGroup at
> >>>>>
> com.whitepages.data.flink.Resolution$.pipeline(Resolution.scala:123)) ->
> >>>>> Filter (Filter at
> >>>>>
> com.whitepages.data.flink.Resolution$.pipeline(Resolution.scala:124))' ,
> >>>>> caused an error: Error obtaining the sorted input: Thread 'SortMerger
> >>>>> Reading Thread' terminated due to an exception: No more bytes left.
> >>>>> at
> org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:455)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.BatchTask.invoke(BatchTask.java:345)
> >>>>> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:559)
> >>>>> at java.lang.Thread.run(Thread.java:745)
> >>>>> Caused by: java.lang.RuntimeException: Error obtaining the sorted
> >>>>> input: Thread 'SortMerger Reading Thread' terminated due to an
> exception: No
> >>>>> more bytes left.
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger.getIterator(UnilateralSortMerger.java:619)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.BatchTask.getInput(BatchTask.java:1079)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.CoGroupDriver.prepare(CoGroupDriver.java:97)
> >>>>> at
> org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:450)
> >>>>> ... 3 more
> >>>>> Caused by: java.io.IOException: Thread 'SortMerger Reading Thread'
> >>>>> terminated due to an exception: No more bytes left.
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger$ThreadBase.run(UnilateralSortMerger.java:799)
> >>>>> Caused by: java.io.EOFException: No more bytes left.
> >>>>> at
> >>>>>
> org.apache.flink.api.java.typeutils.runtime.NoFetchingInput.require(NoFetchingInput.java:77)
> >>>>> at com.esotericsoftware.kryo.io.Input.readUtf8_slow(Input.java:542)
> >>>>> at com.esotericsoftware.kryo.io.Input.readUtf8(Input.java:535)
> >>>>> at com.esotericsoftware.kryo.io.Input.readString(Input.java:465)
> >>>>> at
> >>>>>
> com.esotericsoftware.kryo.serializers.UnsafeCacheFields$UnsafeStringField.read(UnsafeCacheFields.java:198)
> >>>>> at
> >>>>>
> com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:528)
> >>>>> at com.esotericsoftware.kryo.Kryo.readClassAndObject(Kryo.java:764)
> >>>>> at
> >>>>>
> org.apache.flink.api.java.typeutils.runtime.kryo.KryoSerializer.deserialize(KryoSerializer.java:228)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.typeutils.OptionSerializer.deserialize(OptionSerializer.scala:67)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.typeutils.OptionSerializer.deserialize(OptionSerializer.scala:28)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.typeutils.CaseClassSerializer.deserialize(CaseClassSerializer.scala:113)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.typeutils.CaseClassSerializer.deserialize(CaseClassSerializer.scala:106)
> >>>>> at
> >>>>>
> org.apache.flink.api.scala.typeutils.CaseClassSerializer.deserialize(CaseClassSerializer.scala:30)
> >>>>> at
> >>>>>
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.deserialize(TupleSerializer.java:144)
> >>>>> at
> >>>>>
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.deserialize(TupleSerializer.java:30)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.plugable.ReusingDeserializationDelegate.read(ReusingDeserializationDelegate.java:57)
> >>>>> at
> >>>>> org.apache.flink.runtime.io
> .network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer.getNextRecord(SpillingAdaptiveSpanningRecordDeserializer.java:163)
> >>>>> at
> >>>>> org.apache.flink.runtime.io
> .network.api.reader.AbstractRecordReader.getNextRecord(AbstractRecordReader.java:65)
> >>>>> at
> >>>>> org.apache.flink.runtime.io
> .network.api.reader.MutableRecordReader.next(MutableRecordReader.java:34)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.util.ReaderIterator.next(ReaderIterator.java:59)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger$ReadingThread.go(UnilateralSortMerger.java:1035)
> >>>>> at
> >>>>>
> org.apache.flink.runtime.operators.sort.UnilateralSortMerger$ThreadBase.run(UnilateralSortMerger.java:796)
> >>>>>
> >>>>> The simplified version of the code looks more or less like following:
> >>>>> ```
> >>>>> case class Name(first: String, last: String)
> >>>>> case class Phone(number: String)
> >>>>> case class Address(addr: String, city: String, country: String)
> >>>>> case class Record(n: Name, phone: Option[Phone], addr:
> Option[Address])
> >>>>> ...
> >>>>> def resolutionFunc: (Iterator[Record], Iterator[(Name, String)] =>
> >>>>> String = ...
> >>>>> ...
> >>>>> val data = env.readCsvFile[MySchema](...).map(Record(_))
> >>>>>
> >>>>> val helper: DataSet[(Name, String)] = ...
> >>>>>
> >>>>> val result = data.filter(_.address.isDefined)
> >>>>> .coGroup(helper)
> >>>>> .where(e => LegacyDigest.buildMessageDigest((e.name,
> >>>>> e.address.get.country)))
> >>>>> .equalTo(e => LegacyDigest.buildMessageDigest((e._1, e._2)))
> >>>>> .apply {resolutionFunc}
> >>>>> .filter(_ != "")
> >>>>>
> >>>>> result.writeAsText(...)
> >>>>> ```
> >>>>>
> >>>>> This code fails only when I run it on the full dataset, when I split
> >>>>> the `data` on smaller chunks (`helper` always stays the same), I'm
> able to
> >>>>> complete successfully. I guess with smaller memory requirements
> >>>>> serialization/deserialization does not kick in.
> >>>>>
> >>>>> I'm trying now to explicitly set Protobuf serializer for Kryo:
> >>>>> ```
> >>>>> env.getConfig.registerTypeWithKryoSerializer(classOf[Record],
> >>>>> classOf[ProtobufSerializer])
> >>>>>
> >>>>> ```
> >>>>> but every run takes significant time before failing, so any other
> >>>>> advice is appreciated.
> >>>>>
> >>>>> Thanks,
> >>>>> Timur
> >>>>
> >>>>
> >>>
> >>
> >
>
