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https://issues.apache.org/jira/browse/KAFKA-1710?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14183775#comment-14183775
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Jay Kreps commented on KAFKA-1710:
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You could try some profiling and see if you see any implementation bottlenecks.
I don't think we can fundamentally reengineer this piece or move the
compression outside the lock. The reason being that you have multiple threads
that want to write to a shared byte array. We need to synchronized access to
ensure safety (otherwise they would overwrite each others data). Furthermore
since this is batch compression we are compressing into the destination array
using a compressor used for the prior messages. This batch compression is very
important to get a good compression ratio as it allows redundancy between
messages to be exploited.
> [New Java Producer Potential Deadlock] Producer Deadlock when all messages is
> being sent to single partition
> ------------------------------------------------------------------------------------------------------------
>
> Key: KAFKA-1710
> URL: https://issues.apache.org/jira/browse/KAFKA-1710
> Project: Kafka
> Issue Type: Bug
> Components: producer
> Environment: Development
> Reporter: Bhavesh Mistry
> Assignee: Ewen Cheslack-Postava
> Priority: Critical
> Labels: performance
> Attachments: Screen Shot 2014-10-13 at 10.19.04 AM.png, Screen Shot
> 2014-10-15 at 9.09.06 PM.png, Screen Shot 2014-10-15 at 9.14.15 PM.png,
> TestNetworkDownProducer.java, th1.dump, th10.dump, th11.dump, th12.dump,
> th13.dump, th14.dump, th15.dump, th2.dump, th3.dump, th4.dump, th5.dump,
> th6.dump, th7.dump, th8.dump, th9.dump
>
>
> Hi Kafka Dev Team,
> When I run the test to send message to single partition for 3 minutes or so
> on, I have encounter deadlock (please see the screen attached) and thread
> contention from YourKit profiling.
> Use Case:
> 1) Aggregating messages into same partition for metric counting.
> 2) Replicate Old Producer behavior for sticking to partition for 3 minutes.
> Here is output:
> Frozen threads found (potential deadlock)
>
> It seems that the following threads have not changed their stack for more
> than 10 seconds.
> These threads are possibly (but not necessarily!) in a deadlock or hung.
>
> pool-1-thread-128 <--- Frozen for at least 2m
> org.apache.kafka.clients.producer.internals.RecordAccumulator.append(TopicPartition,
> byte[], byte[], CompressionType, Callback) RecordAccumulator.java:139
> org.apache.kafka.clients.producer.KafkaProducer.send(ProducerRecord,
> Callback) KafkaProducer.java:237
> org.kafka.test.TestNetworkDownProducer$MyProducer.run()
> TestNetworkDownProducer.java:84
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker)
> ThreadPoolExecutor.java:1145
> java.util.concurrent.ThreadPoolExecutor$Worker.run()
> ThreadPoolExecutor.java:615
> java.lang.Thread.run() Thread.java:744
> pool-1-thread-159 <--- Frozen for at least 2m 1 sec
> org.apache.kafka.clients.producer.internals.RecordAccumulator.append(TopicPartition,
> byte[], byte[], CompressionType, Callback) RecordAccumulator.java:139
> org.apache.kafka.clients.producer.KafkaProducer.send(ProducerRecord,
> Callback) KafkaProducer.java:237
> org.kafka.test.TestNetworkDownProducer$MyProducer.run()
> TestNetworkDownProducer.java:84
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker)
> ThreadPoolExecutor.java:1145
> java.util.concurrent.ThreadPoolExecutor$Worker.run()
> ThreadPoolExecutor.java:615
> java.lang.Thread.run() Thread.java:744
> pool-1-thread-55 <--- Frozen for at least 2m
> org.apache.kafka.clients.producer.internals.RecordAccumulator.append(TopicPartition,
> byte[], byte[], CompressionType, Callback) RecordAccumulator.java:139
> org.apache.kafka.clients.producer.KafkaProducer.send(ProducerRecord,
> Callback) KafkaProducer.java:237
> org.kafka.test.TestNetworkDownProducer$MyProducer.run()
> TestNetworkDownProducer.java:84
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker)
> ThreadPoolExecutor.java:1145
> java.util.concurrent.ThreadPoolExecutor$Worker.run()
> ThreadPoolExecutor.java:615
> java.lang.Thread.run() Thread.java:744
> Thanks,
> Bhavesh
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