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https://issues.apache.org/jira/browse/FLINK-10367?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16644580#comment-16644580
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zhijiang commented on FLINK-10367:
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Good point!
I have not thought of returning this {{NotificationResult}} hint to handle the
results in loop way which can avoid recursive calling from
{{notifyBufferAvailable}}. This way is actually better and can solve the
recursive issues for all the cases. :) (y)
> Avoid recursion stack overflow during releasing SingleInputGate
> ---------------------------------------------------------------
>
> Key: FLINK-10367
> URL: https://issues.apache.org/jira/browse/FLINK-10367
> Project: Flink
> Issue Type: Improvement
> Components: Network
> Affects Versions: 1.5.0, 1.5.1, 1.5.2, 1.5.3, 1.6.0
> Reporter: zhijiang
> Assignee: zhijiang
> Priority: Minor
>
> For task failure or canceling, the {{SingleInputGate#releaseAllResources}}
> will be invoked before task exits.
> In the process of {{SingleInputGate#releaseAllResources}}, we first loop to
> release all the input channels, then destroy the {{BufferPool}}. For
> {{RemoteInputChannel#releaseAllResources}}, it will return floating buffers
> to the {{BufferPool}} {{which assigns this recycled buffer to the other
> listeners(RemoteInputChannel}}).
> It may exist recursive call in this process. If the listener is already
> released before, it will directly recycle this buffer to the {{BufferPool}}
> which takes another listener to notify available buffer. The above process
> may be invoked repeatedly in recursive way.
> If there are many input channels as listeners in the {{BufferPool}}, it will
> cause {{StackOverflow}} error because of recursion. And in our testing job,
> the scale of 10,000 input channels ever caused this error.
> I think of two ways for solving this potential problem:
> # When the input channel is released, it should notify the {{BufferPool}} of
> unregistering this listener, otherwise it is inconsistent between them.
> # {{SingleInputGate}} should destroy the {{BufferPool}} first, then loop to
> release all the internal input channels. To do so, all the listeners in
> {{BufferPool}} will be removed during destroying, and the input channel will
> not have further interactions during
> {{RemoteInputChannel#releaseAllResources}}.
> I prefer the second way to solve this problem, because we do not want to
> expand another interface method for removing buffer listener, further
> currently the internal data structure in {{BufferPool}} can not support
> remove a listener directly.
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