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https://issues.apache.org/jira/browse/CASSANDRA-3294?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13217235#comment-13217235
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Brandon Williams commented on CASSANDRA-3294:
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bq. How about we assign probability "to be alive" to each of the nodes in the
ring
This sounds like reinventing the existing failure detector to me.
> a node whose TCP connection is not up should be considered down for the
> purpose of reads and writes
> ---------------------------------------------------------------------------------------------------
>
> Key: CASSANDRA-3294
> URL: https://issues.apache.org/jira/browse/CASSANDRA-3294
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Peter Schuller
> Assignee: Peter Schuller
>
> Cassandra fails to handle the most simple of cases intelligently - a process
> gets killed and the TCP connection dies. I cannot see a good reason to wait
> for a bunch of RPC timeouts and thousands of hung requests to realize that we
> shouldn't be sending messages to a node when the only possible means of
> communication is confirmed down. This is why one has to "disablegossip and
> wait for a while" to restar a node on a busy cluster (especially without
> CASSANDRA-2540 but that only helps under certain circumstances).
> A more generalized approach where by one e.g. weights in the number of
> currently outstanding RPC requests to a node, would likely take care of this
> case as well. But until such a thing exists and works well, it seems prudent
> to have the very common and controlled form of "failure" be handled better.
> Are there difficulties I'm not seeing?
> I can see that one may want to distinguish between considering something
> "really down" (and e.g. fail a repair because it's down) from what I'm
> talking about, so maybe there are different concepts (say one is "currently
> unreachable" rather than "down") being conflated. But in the specific case of
> sending reads/writes to a node we *know* we cannot talk to, it seems
> unnecessarily detrimental.
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