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https://issues.apache.org/jira/browse/CASSANDRA-17324?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17484008#comment-17484008
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Brandon Williams commented on CASSANDRA-17324:
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This makes sense, then. Reads can be avoided since all replicas aren't needed,
but writes don't have that luxury.
> Allow node to reject internode messages that create work for the MUTATION
> stage
> -------------------------------------------------------------------------------
>
> Key: CASSANDRA-17324
> URL: https://issues.apache.org/jira/browse/CASSANDRA-17324
> Project: Cassandra
> Issue Type: Improvement
> Components: Messaging/Internode
> Reporter: Caleb Rackliffe
> Assignee: Caleb Rackliffe
> Priority: Normal
> Fix For: 4.x
>
>
> When a node is struggling under the weight of a compaction backlog and
> becomes a cause of increased read latency for clients, we have two safety
> valves:
> 1.) Disabling the native protocol server, which stops the node from
> coordinating reads and writes.
> 2.) Jacking up the severity on the node, which tells the dynamic snitch to
> avoid the node for reads from other coordinators.
> These are useful, but we don’t appear to have any mechanism that would allow
> us to temporarily reject internode hint, batch, and mutation messages that
> could further delay resolution of the compaction backlog. There is a
> parameter in {{cassandra.yaml}} called {{hinted_handoff_throttle}} (formerly
> {{hinted_handoff_throttle_in_kb}}) that allows us to control the rate at
> which we read hints before they are delivered, but how fast that should
> happen and whether it should happen at all are two different questions.
> The proposal here is to add this rejection mechanism and publish it via JMX,
> along with any metrics and logging that would be necessary to make its
> effects visible. (Ex. Hint delivery already has metrics around success,
> failure, and timeouts, which would be helpful around this.) The
> error-handling pathways for hints, writes, and batches should already be
> capable of handling one more type of error (i.e. “that replica is
> overloaded”), but some non-spammy logging around that probably wouldn’t hurt.
> In implementation space, one idea that would minimize the amount of surgery
> we need to do is making the decision around whether to send back a failure
> message directly in {{InboundSink}}. This would avoid having to duplicate the
> logic in multiple downstream handlers.
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