flink-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Maximilian Michels <...@apache.org>
Subject Re: Bug broadcasting objects (serialization issue)
Date Thu, 03 Sep 2015 08:52:12 GMT
Thanks for clarifying the "eager serialization". By serializing and
deserializing explicitly (eagerly) we can raise better Exceptions to
notify the user of non-serializable classes.

> BTW: There is an opportunity to fix two problems with one patch: The framesize overflow
for the input format, and the serialization.

IMHO this adds another layer of complexity to the job submission
phase. I just had a chat with Robert about this. I wonder, is it
possible to increase the Akka framesize only for the Client
ActorSystem?

On Wed, Sep 2, 2015 at 4:27 PM, Stephan Ewen <sewen@apache.org> wrote:
> I see.
>
> Manual serialization implies also manual deserialization (on the workers
> only), which would give a better exception.
>
> BTW: There is an opportunity to fix two problems with one patch: The
> framesize overflow for the input format, and the serialization.
>
> On Wed, Sep 2, 2015 at 4:16 PM, Maximilian Michels <mxm@apache.org> wrote:
>>
>> Ok but that would not prevent the above error, right? Serializing is
>> not the issue here.
>>
>> Nevertheless, it would catch all errors during initial serialization.
>> Deserializing has its own hazards due to possible Classloader issues.
>>
>> On Wed, Sep 2, 2015 at 4:05 PM, Stephan Ewen <sewen@apache.org> wrote:
>> > Yes, even serialize in the constructor. Then the failure (if
>> > serialization
>> > does not work) comes immediately.
>> >
>> > On Wed, Sep 2, 2015 at 4:02 PM, Maximilian Michels <mxm@apache.org>
>> > wrote:
>> >>
>> >> Nice suggestion. So you want to serialize and deserialize the
>> >> InputFormats
>> >> on the Client to check whether they can be transferred correctly?
>> >> Merely
>> >> serializing is not enough because the above Exception occurs during
>> >> deserialization.
>> >>
>> >> On Wed, Sep 2, 2015 at 2:29 PM, Stephan Ewen <sewen@apache.org> wrote:
>> >>>
>> >>> We should try to improve the exception here. More people will run into
>> >>> this issue and the exception should help them understand it well.
>> >>>
>> >>> How about we do eager serialization into a set of byte arrays? Then
>> >>> the
>> >>> serializability issue comes immediately when the program is
>> >>> constructed,
>> >>> rather than later, when it is shipped.
>> >>>
>> >>> On Wed, Sep 2, 2015 at 12:56 PM, Maximilian Michels <mxm@apache.org>
>> >>> wrote:
>> >>>>
>> >>>> Here's the JIRA issue:
>> >>>> https://issues.apache.org/jira/browse/FLINK-2608
>> >>>>
>> >>>> On Wed, Sep 2, 2015 at 12:49 PM, Maximilian Michels <mxm@apache.org>
>> >>>> wrote:
>> >>>>>
>> >>>>> Hi Andreas,
>> >>>>>
>> >>>>> Thank you for reporting the problem and including the code to
>> >>>>> reproduce
>> >>>>> the problem. I think there is a problem with the class serialization
>> >>>>> or
>> >>>>> deserialization. Arrays.asList uses a private ArrayList class
>> >>>>> (java.util.Arrays$ArrayList) which is not the one you would
normally
>> >>>>> use
>> >>>>> (java.util.ArrayList).
>> >>>>>
>> >>>>> I'll create a JIRA issue to keep track of the problem and to
>> >>>>> investigate further.
>> >>>>>
>> >>>>> Best regards,
>> >>>>> Max
>> >>>>>
>> >>>>> Here's the stack trace:
>> >>>>>
>> >>>>> Exception in thread "main"
>> >>>>> org.apache.flink.runtime.client.JobExecutionException: Cannot
>> >>>>> initialize
>> >>>>> task 'DataSource (at main(Test.java:32)
>> >>>>> (org.apache.flink.api.java.io.CollectionInputFormat))':
>> >>>>> Deserializing the
>> >>>>> InputFormat ([mytests.Test$TestClass@4d6025c5]) failed: unread
block
>> >>>>> data
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$4.apply(JobManager.scala:523)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$4.apply(JobManager.scala:507)
>> >>>>>     at scala.collection.Iterator$class.foreach(Iterator.scala:727)
>> >>>>>     at
>> >>>>> scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
>> >>>>>     at
>> >>>>> scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
>> >>>>>     at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager.org$apache$flink$runtime$jobmanager$JobManager$$submitJob(JobManager.scala:507)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$receiveWithLogMessages$1.applyOrElse(JobManager.scala:190)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.runtime.AbstractPartialFunction$mcVL$sp.apply$mcVL$sp(AbstractPartialFunction.scala:33)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.runtime.AbstractPartialFunction$mcVL$sp.apply(AbstractPartialFunction.scala:33)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.runtime.AbstractPartialFunction$mcVL$sp.apply(AbstractPartialFunction.scala:25)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.ActorLogMessages$$anon$1.apply(ActorLogMessages.scala:43)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.ActorLogMessages$$anon$1.apply(ActorLogMessages.scala:29)
>> >>>>>     at
>> >>>>> scala.PartialFunction$class.applyOrElse(PartialFunction.scala:118)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.ActorLogMessages$$anon$1.applyOrElse(ActorLogMessages.scala:29)
>> >>>>>     at akka.actor.Actor$class.aroundReceive(Actor.scala:465)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager.aroundReceive(JobManager.scala:92)
>> >>>>>     at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)
>> >>>>>     at akka.actor.ActorCell.invoke(ActorCell.scala:487)
>> >>>>>     at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:254)
>> >>>>>     at akka.dispatch.Mailbox.run(Mailbox.scala:221)
>> >>>>>     at akka.dispatch.Mailbox.exec(Mailbox.scala:231)
>> >>>>>     at
>> >>>>> scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
>> >>>>>     at
>> >>>>>
>> >>>>> scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
>> >>>>> Caused by: java.lang.Exception: Deserializing the InputFormat
>> >>>>> ([mytests.Test$TestClass@4d6025c5]) failed: unread block data
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobgraph.InputFormatVertex.initializeOnMaster(InputFormatVertex.java:60)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobmanager.JobManager$$anonfun$org$apache$flink$runtime$jobmanager$JobManager$$submitJob$4.apply(JobManager.scala:520)
>> >>>>>     ... 25 more
>> >>>>> Caused by: java.lang.IllegalStateException: unread block data
>> >>>>>     at
>> >>>>>
>> >>>>> java.io.ObjectInputStream$BlockDataInputStream.setBlockDataMode(ObjectInputStream.java:2424)
>> >>>>>     at
>> >>>>> java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1383)
>> >>>>>     at
>> >>>>>
>> >>>>> java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1993)
>> >>>>>     at
>> >>>>>
>> >>>>> java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1918)
>> >>>>>     at
>> >>>>>
>> >>>>> java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
>> >>>>>     at
>> >>>>> java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
>> >>>>>     at
>> >>>>> java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:302)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.util.InstantiationUtil.readObjectFromConfig(InstantiationUtil.java:264)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.operators.util.TaskConfig.getStubWrapper(TaskConfig.java:282)
>> >>>>>     at
>> >>>>>
>> >>>>> org.apache.flink.runtime.jobgraph.InputFormatVertex.initializeOnMaster(InputFormatVertex.java:57)
>> >>>>>     ... 26 more
>> >>>>>
>> >>>>> On Wed, Sep 2, 2015 at 11:17 AM, Andres R. Masegosa
>> >>>>> <andres@cs.aau.dk>
>> >>>>> wrote:
>> >>>>>>
>> >>>>>> Hi,
>> >>>>>>
>> >>>>>> I get a bug when trying to broadcast a list of integers
created
>> >>>>>> with
>> >>>>>> the
>> >>>>>> primitive "Arrays.asList(...)".
>> >>>>>>
>> >>>>>> For example, if you try to run this "wordcount" example,
you can
>> >>>>>> reproduce the bug.
>> >>>>>>
>> >>>>>>
>> >>>>>> public class WordCountExample {
>> >>>>>>     public static void main(String[] args) throws Exception
{
>> >>>>>>         final ExecutionEnvironment env =
>> >>>>>> ExecutionEnvironment.getExecutionEnvironment();
>> >>>>>>
>> >>>>>>     DataSet<String> text = env.fromElements(
>> >>>>>>                 "Who's there?",
>> >>>>>>                 "I think I hear them. Stand, ho! Who's there?");
>> >>>>>>
>> >>>>>>         List<Integer> elements = Arrays.asList(0,
0, 0);
>> >>>>>>
>> >>>>>>         DataSet<TestClass> set = env.fromElements(new
>> >>>>>> TestClass(elements));
>> >>>>>>
>> >>>>>>         DataSet<Tuple2<String, Integer>> wordCounts
= text
>> >>>>>>                 .flatMap(new LineSplitter())
>> >>>>>>                 .withBroadcastSet(set, "set")
>> >>>>>>                 .groupBy(0)
>> >>>>>>                 .sum(1);
>> >>>>>>
>> >>>>>>         wordCounts.print();
>> >>>>>>     }
>> >>>>>>
>> >>>>>>     public static class LineSplitter implements
>> >>>>>> FlatMapFunction<String,
>> >>>>>> Tuple2<String, Integer>> {
>> >>>>>>         @Override
>> >>>>>>         public void flatMap(String line, Collector<Tuple2<String,
>> >>>>>> Integer>> out) {
>> >>>>>>             for (String word : line.split(" ")) {
>> >>>>>>                 out.collect(new Tuple2<String, Integer>(word,
1));
>> >>>>>>             }
>> >>>>>>         }
>> >>>>>>     }
>> >>>>>>
>> >>>>>>     public static class TestClass implements Serializable
{
>> >>>>>>         private static final long serialVersionUID =
>> >>>>>> -2932037991574118651L;
>> >>>>>>
>> >>>>>>         List<Integer> integerList;
>> >>>>>>         public TestClass(List<Integer> integerList){
>> >>>>>>             this.integerList=integerList;
>> >>>>>>         }
>> >>>>>>
>> >>>>>>
>> >>>>>>     }
>> >>>>>> }
>> >>>>>>
>> >>>>>>
>> >>>>>> However, if instead of using the primitive "Arrays.asList(...)",
we
>> >>>>>> use
>> >>>>>> instead the ArrayList<> constructor, there is any
problem!!!!
>> >>>>>>
>> >>>>>>
>> >>>>>> Regards,
>> >>>>>> Andres
>> >>>>>
>> >>>>>
>> >>>>
>> >>>
>> >>
>> >
>
>

Mime
View raw message