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https://issues.apache.org/jira/browse/CASSANDRA-2045?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13057348#comment-13057348
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Jonathan Ellis commented on CASSANDRA-2045:
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bq. I was under the impression that HintedHandoff helps to retain the
replication factor even in the face of failed replicas.
Nope. If you require N replicas to be written, then you should use an
appropriate consistency level.
In 0.6+ hints are stored to other live replicas whenever possible (i.e. you
still have less total replicas written) unless, as you noted, no replicas are
alive and you're writing at CL.ANY.
So my point is that after we move away from storing hints as pointers to row
data, there's no reason for the "prefer other replicas" optimization so we
might as well just always store it on the coordinator.
> Simplify HH to decrease read load when nodes come back
> ------------------------------------------------------
>
> Key: CASSANDRA-2045
> URL: https://issues.apache.org/jira/browse/CASSANDRA-2045
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Chris Goffinet
> Assignee: Nicholas Telford
> Fix For: 1.0
>
> Attachments:
> 0001-Changed-storage-of-Hints-to-store-a-serialized-RowMu.patch,
> 0002-Refactored-HintedHandoffManager.sendRow-to-reduce-co.patch,
> 0003-Fixed-some-coding-style-issues.patch,
> 0004-Fixed-direct-usage-of-Gossiper.getEndpointStateForEn.patch,
> 0005-Removed-duplicate-failure-detection-conditionals.-It.patch,
> 0006-Removed-handling-of-old-style-hints.patch, 2045-v3.txt,
> CASSANDRA-2045-simplify-hinted-handoff-001.diff,
> CASSANDRA-2045-simplify-hinted-handoff-002.diff
>
>
> Currently when HH is enabled, hints are stored, and when a node comes back,
> we begin sending that node data. We do a lookup on the local node for the row
> to send. To help reduce read load (if a node is offline for long period of
> time) we should store the data we want forward the node locally instead. We
> wouldn't have to do any lookups, just take byte[] and send to the destination.
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