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https://issues.apache.org/jira/browse/CASSANDRA-6746?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13915986#comment-13915986
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Benedict commented on CASSANDRA-6746:
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bq. Now I wonder if that's deliberate or an oversight.
I remember seeing a comment somewhere stating the rationale was to avoid
polluting the page cache with stale data, but now I can't find it, so I wonder
if I imagined it. That is what I based my prior statement on :-|
bq. Incidentally, I'm inclined to think that we should make the default "leave
it alone" and change the option to be normal/dontneed/willneed instead.
I agree. I think the best default we can do is leave alone unless we really
know we DONTNEED (i.e. we never intend to look at it again)
> Reads have a slow ramp up in speed
> ----------------------------------
>
> Key: CASSANDRA-6746
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6746
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Ryan McGuire
> Assignee: Benedict
> Labels: performance
> Fix For: 2.1 beta2
>
> Attachments: 2.1_vs_2.0_read.png,
> cassandra-2.0-bdplab-trial-fincore.tar.bz2,
> cassandra-2.1-bdplab-trial-fincore.tar.bz2
>
>
> On a physical four node cluister I am doing a big write and then a big read.
> The read takes a long time to ramp up to respectable speeds.
> !2.1_vs_2.0_read.png!
> [See data
> here|http://ryanmcguire.info/ds/graph/graph.html?stats=stats.2.1_vs_2.0_vs_1.2.retry1.json&metric=interval_op_rate&operation=stress-read&smoothing=1]
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