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https://issues.apache.org/jira/browse/CASSANDRA-2034?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13073807#comment-13073807
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Patricio Echague commented on CASSANDRA-2034:
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{quote} Does the timeout on get start when the future is created, or when get
is called? I think it is the latter but I am not sure. If so, we should track
the total time waited and reduce after each get() so we do not allow total of
up to timeout * hints. {quote}
Yeah, I need to add a creation time and so something similar to what
IAsynResult does.
I noticed I missed to skip the hints creation when HH is disabled.
Some thoughts on this I would like some feedback:
Note: remember that hints are written locally on the coordinator node now.
| Hinted Handoff | Consist. Level |
| on | >=1 | --> wait for hints. We DO NOT notify the
handler with handler.response() for hints;
| on | ANY | --> wait for hints. Responses count towards
consistency.
| off | >=1 | --> DO NOT fire hints. And DO NOT wait for
them to complete.
| off | ANY | --> Fire hints but don't wait for them.
They count towards consistency.
> Make Read Repair unnecessary when Hinted Handoff is enabled
> -----------------------------------------------------------
>
> Key: CASSANDRA-2034
> URL: https://issues.apache.org/jira/browse/CASSANDRA-2034
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Jonathan Ellis
> Assignee: Patricio Echague
> Fix For: 1.0
>
> Attachments: CASSANDRA-2034-trunk.patch
>
> Original Estimate: 8h
> Remaining Estimate: 8h
>
> Currently, HH is purely an optimization -- if a machine goes down, enabling
> HH means RR/AES will have less work to do, but you can't disable RR entirely
> in most situations since HH doesn't kick in until the FailureDetector does.
> Let's add a scheduled task to the mutate path, such that we return to the
> client normally after ConsistencyLevel is achieved, but after RpcTimeout we
> check the responseHandler write acks and write local hints for any missing
> targets.
> This would making disabling RR when HH is enabled a much more reasonable
> option, which has a huge impact on read throughput.
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