Hi, this looks like a potential Flink bug. Looping in Nico and Piotr who have looked into that in the past. Could you please comment on that?
Best, Aljoscha > On 3. Oct 2018, at 12:12, Narayanaswamy, Krishna > <krishna.narayanasw...@gs.com> wrote: > > Hi, > > I am trying to run one large single job graph which has > 10k tasks. The form > of the graph is something like > DataSource -> Filter -> Map [...multiple] > Sink1 > Sink2 > I am using a parallelism of 10 with 1 slot per task manager and a memory > allocation of 32G per TM. The JM is running with 8G. > > Everything starts up and runs fine with close to 6-7k tasks (this is variable > and is mostly the source /filter/map portions) completing and then the graph > just hangs. I managed to connect to the task managers and get a thread dump > just in time and found the following deadlock on one of the TMs which > apparently seems to be holding up everything else. > Please could someone take a look and advise if there is something I could do > or try out to fix this. > > Marked below are the 2 isolated thread stacks marking the deadlock - > > Thread-1 > "DataSink (DATA#HadoopFileOutputFormat ) (1/2)@11002" prio=5 tid=0x3e2 nid=NA > waiting for monitor entry > waiting for Map (Key Extractor) (1/10)@9967 to release lock on > <0x2dfb> (a java.util.ArrayDeque) > at > org.apache.flink.runtime.io.network.partition.SpillableSubpartition.releaseMemory(SpillableSubpartition.java:223) > at > org.apache.flink.runtime.io.network.partition.ResultPartition.releaseMemory(ResultPartition.java:373) > at > org.apache.flink.runtime.io.network.buffer.LocalBufferPool.setNumBuffers(LocalBufferPool.java:355) > - locked <0x2dfd> (a java.util.ArrayDeque) > at > org.apache.flink.runtime.io.network.buffer.NetworkBufferPool.redistributeBuffers(NetworkBufferPool.java:402) > at > org.apache.flink.runtime.io.network.buffer.NetworkBufferPool.recycleMemorySegments(NetworkBufferPool.java:203) > - locked <0x2da5> (a java.lang.Object) > at > org.apache.flink.runtime.io.network.buffer.NetworkBufferPool.recycleMemorySegments(NetworkBufferPool.java:193) > at > org.apache.flink.runtime.io.network.partition.consumer.SingleInputGate.returnExclusiveSegments(SingleInputGate.java:318) > at > org.apache.flink.runtime.io.network.partition.consumer.RemoteInputChannel.releaseAllResources(RemoteInputChannel.java:259) > at > org.apache.flink.runtime.io.network.partition.consumer.SingleInputGate.getNextBufferOrEvent(SingleInputGate.java:578) > at > org.apache.flink.runtime.io.network.partition.consumer.SingleInputGate.pollNextBufferOrEvent(SingleInputGate.java:507) > at > org.apache.flink.runtime.io.network.partition.consumer.UnionInputGate.waitAndGetNextInputGate(UnionInputGate.java:213) > at > org.apache.flink.runtime.io.network.partition.consumer.UnionInputGate.getNextBufferOrEvent(UnionInputGate.java:163) > at > org.apache.flink.runtime.io.network.api.reader.AbstractRecordReader.getNextRecord(AbstractRecordReader.java:86) > at > org.apache.flink.runtime.io.network.api.reader.MutableRecordReader.next(MutableRecordReader.java:47) > at > org.apache.flink.runtime.operators.util.ReaderIterator.next(ReaderIterator.java:73) > at > org.apache.flink.runtime.operators.DataSinkTask.invoke(DataSinkTask.java:216) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:703) > at java.lang.Thread.run(Thread.java:745) > > > Thread-2 > "Map (Key Extractor) (1/10)@9967" prio=5 tid=0xaab nid=NA waiting for monitor > entry > java.lang.Thread.State: BLOCKED > blocks DataSink (DATA#HadoopFileOutputFormat ) (1/2)@11002 > waiting for DataSink (DATA#HadoopFileOutputFormat ) (1/2)@11002 to > release lock on <0x2dfd> (a java.util.ArrayDeque) > at > org.apache.flink.runtime.io.network.buffer.LocalBufferPool.recycle(LocalBufferPool.java:261) > at > org.apache.flink.runtime.io.network.buffer.NetworkBuffer.deallocate(NetworkBuffer.java:171) > at > org.apache.flink.shaded.netty4.io.netty.buffer.AbstractReferenceCountedByteBuf.release(AbstractReferenceCountedByteBuf.java:106) > at > org.apache.flink.runtime.io.network.buffer.NetworkBuffer.recycleBuffer(NetworkBuffer.java:146) > at > org.apache.flink.runtime.io.network.buffer.BufferConsumer.close(BufferConsumer.java:110) > at > org.apache.flink.runtime.io.network.partition.SpillableSubpartition.spillFinishedBufferConsumers(SpillableSubpartition.java:271) > at > org.apache.flink.runtime.io.network.partition.SpillableSubpartition.add(SpillableSubpartition.java:117) > - locked <0x2dfb> (a java.util.ArrayDeque) > at > org.apache.flink.runtime.io.network.partition.SpillableSubpartition.add(SpillableSubpartition.java:96) > - locked <0x2dfc> (a > org.apache.flink.runtime.io.network.partition.SpillableSubpartition) > at > org.apache.flink.runtime.io.network.partition.ResultPartition.addBufferConsumer(ResultPartition.java:255) > at > org.apache.flink.runtime.io.network.api.writer.RecordWriter.requestNewBufferBuilder(RecordWriter.java:211) > at > org.apache.flink.runtime.io.network.api.writer.RecordWriter.sendToTarget(RecordWriter.java:142) > at > org.apache.flink.runtime.io.network.api.writer.RecordWriter.emit(RecordWriter.java:105) > at > org.apache.flink.runtime.operators.shipping.OutputCollector.collect(OutputCollector.java:65) > at > org.apache.flink.runtime.operators.util.metrics.CountingCollector.collect(CountingCollector.java:35) > at > org.apache.flink.runtime.operators.MapDriver.run(MapDriver.java:103) > at > org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:503) > at > org.apache.flink.runtime.operators.BatchTask.invoke(BatchTask.java:368) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:703) > at java.lang.Thread.run(Thread.java:745) > > Thanks, > Krishna. > > > ________________________________ > > Your Personal Data: We may collect and process information about you that may > be subject to data protection laws. For more information about how we use and > disclose your personal data, how we protect your information, our legal basis > to use your information, your rights and who you can contact, please refer > to: www.gs.com/privacy-notices <http://www.gs.com/privacy-notices>
