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https://issues.apache.org/jira/browse/CASSANDRA-6127?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13811823#comment-13811823
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Quentin Conner commented on CASSANDRA-6127:
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Monday (11/4) I will be start getting the CPU profiling captured with a 256 or
512 node cluster. Plan is to capture with internode compression and without.
I was able to get semi-reproduction this week in a 256 node cluster -- one node
had twice the cpu utilization of the others (20% user versus 10% user). But I
had too much logging enabled and that skewed results.
> 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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