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https://issues.apache.org/jira/browse/CASSANDRA-6127?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13805838#comment-13805838
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Quentin Conner commented on CASSANDRA-6127:
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I grabbed some sample log files from 10 nodes of 256 in a run today.
[flap-intervals.tar.gz|http://qconner.s3.amazonaws.com/flap-intervals.tar.gz]
Convictions are happening with only 1 to 5 intervals recorded. Patch #3 is
looking like the winner but we should do the math by hand to be sure
(volunteers?).
Also, I just tested [Patch
#3|https://issues.apache.org/jira/secure/attachment/12610117/delayEstimatorUntilStatisticallyValid.patch]
and found 0 flaps for the same setup as yesterday (256 nodes, phi=8, normal
1000 ms gossip period).
> vnodes don't scale to hundreds of nodes
> ---------------------------------------
>
> Key: CASSANDRA-6127
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6127
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Environment: Any cluster that has vnodes and consists of hundreds of
> physical nodes.
> Reporter: Tupshin Harper
> Assignee: Jonathan Ellis
> Attachments: 6000vnodes.patch, AdjustableGossipPeriod.patch,
> delayEstimatorUntilStatisticallyValid.patch
>
>
> There are a lot of gossip-related issues related to very wide clusters that
> also have vnodes enabled. Let's use this ticket as a master in case there are
> sub-tickets.
> The most obvious symptom I've seen is with 1000 nodes in EC2 with m1.xlarge
> instances. Each node configured with 32 vnodes.
> Without vnodes, cluster spins up fine and is ready to handle requests within
> 30 minutes or less.
> With vnodes, nodes are reporting constant up/down flapping messages with no
> external load on the cluster. After a couple of hours, they were still
> flapping, had very high cpu load, and the cluster never looked like it was
> going to stabilize or be useful for traffic.
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