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https://issues.apache.org/jira/browse/FLINK-14872?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16979191#comment-16979191
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Yingjie Cao commented on FLINK-14872:
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[~pnowojski] They are relevant and the causes are similar though not exactly
the same. Even with the timeout fix, there is still deadlock problem.
The issue reported in FLINK-12852 is because the down stream relies the
upstream to release Buffer, but the upstream relies downstream to consume data
before recycling Buffers.
The issue reported in this Jira is because the ResultPartition relies the
InputGate to release Buffer, but the InputGate relies the data to be processed
and emitted to ResultPartition.
> Potential deadlock for task reading from blocking ResultPartition.
> ------------------------------------------------------------------
>
> Key: FLINK-14872
> URL: https://issues.apache.org/jira/browse/FLINK-14872
> Project: Flink
> Issue Type: Bug
> Reporter: Yingjie Cao
> Priority: Blocker
> Fix For: 1.10.0
>
>
> Currently, the buffer pool size of InputGate reading from blocking
> ResultPartition is unbounded which have a potential of using too many buffers
> and may lead to ResultPartition of the same task can not acquire enough core
> buffers and finally lead to deadlock.
> Considers the following case:
> Core buffers are reserved for InputGate and ResultPartition -> InputGate
> consumes lots of Buffer (not including the buffer reserved for
> ResultPartition) -> Other tasks acquire exclusive buffer for InputGate and
> trigger redistribute of Buffers (Buffers taken by previous InputGate can not
> be released) -> The first task of which InputGate uses lots of buffers begin
> to emit records but can not acquire enough core Buffers (Some operators may
> not emit records out immediately or there is just nothing to emit) ->
> Deadlock.
>
> I think we can fix this problem by limit the number of Buffers can be
> allocated by a InputGate which reads from blocking ResultPartition.
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