[
https://issues.apache.org/jira/browse/FLINK-6613?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16022285#comment-16022285
]
Tzu-Li (Gordon) Tai edited comment on FLINK-6613 at 5/24/17 4:12 AM:
---------------------------------------------------------------------
. + 1 to what [~rmetzger] mentioned. The Kafka consumer (0.9+) will always have
as much as 2 {{ConsumerRecords}}, one in the {{Handover}} awaiting to be
processed, another awaiting to be added to {{Handover}} in the
{{KafkaConsumerThread}}.
Regarding what you expect:
"2) Read next batch of messages only when previous batch processed" --> this is
already what is happening, with only a size 1 buffer in the {{Handover}}. Also,
I don't think it will solve the root cause of whats causing your OOM, even if
we remove buffering completely.
"1) KafkaConsumerThread read messages with total size ~1G." --> as Robert
mentioned, you should be able to just directly configure the Kafka client for
that, and will likely solve your problem.
was (Author: tzulitai):
. + 1 to what [~rmetzger] mentioned. The Kafka consumer (0.9+) will always have
as much as 2 {{ConsumerRecords}}, one in the {{Handover}} awaiting to be
processed, another awaiting to be added to {{Handover}}.
Regarding what you expect:
"2) Read next batch of messages only when previous batch processed" --> this is
already what is happening, with only a size 1 buffer in the {{Handover}}. Also,
I don't think it will solve the root cause of whats causing your OOM, even if
we remove buffering completely.
"1) KafkaConsumerThread read messages with total size ~1G." --> as Robert
mentioned, you should be able to just directly configure the Kafka client for
that, and will likely solve your problem.
> OOM during reading big messages from Kafka
> ------------------------------------------
>
> Key: FLINK-6613
> URL: https://issues.apache.org/jira/browse/FLINK-6613
> Project: Flink
> Issue Type: Bug
> Components: Kafka Connector
> Affects Versions: 1.2.0
> Reporter: Andrey
>
> Steps to reproduce:
> 1) Setup Task manager with 2G heap size
> 2) Setup job that reads messages from Kafka 10 (i.e. FlinkKafkaConsumer010)
> 3) Send 3300 messages each 635Kb. So total size is ~2G
> 4) OOM in task manager.
> According to heap dump:
> 1) KafkaConsumerThread read messages with total size ~1G.
> 2) Pass them to the next operator using
> org.apache.flink.streaming.connectors.kafka.internal.Handover
> 3) Then began to read another batch of messages.
> 4) Task manager was able to read next batch of ~500Mb messages until OOM.
> Expected:
> 1) Either have constraint like "number of messages in-flight" OR
> 2) Read next batch of messages only when previous batch processed OR
> 3) Any other option which will solve OOM.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
