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https://issues.apache.org/jira/browse/CASSANDRA-9558?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14614813#comment-14614813
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Benedict commented on CASSANDRA-9558:
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bq. The problem does not exist with Cassandra because it's a server, both the
producer and the consumer is the event loop.
They aren't, but there is a bound on the number of concurrent connections we
can be processing requests for on the server, and so the queue size must itself
be bounded.
I would also suggest imposing a user-configurable bound on the size of your
queues in the driver (or the total number of not-yet-sent messages), as there
can be a multitude of reasons for the message queues to back up, and that's
independently bad for the health of the application process. That wouldn't
solve this problem, but it would have likely helped a great deal, and is
something to consider as well (especially as we may start blocking receipt of
messages to cope with cluster overload, which would translate to a growing
application send buffer).
Either way, good catch. Looks like the fix should be simple (let's hope it
brings throughput right back up).
> Cassandra-stress regression in 2.2
> ----------------------------------
>
> Key: CASSANDRA-9558
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9558
> Project: Cassandra
> Issue Type: Bug
> Reporter: Alan Boudreault
> Assignee: Andy Tolbert
> Fix For: 2.2.0 rc2
>
> Attachments: 2.1.log, 2.2.log, CASSANDRA-9558-2.patch,
> CASSANDRA-9558-ProtocolV2.patch, atolber-CASSANDRA-9558-stress.tgz,
> atolber-trunk-driver-coalescing-disabled.txt,
> stress-2.1-java-driver-2.0.9.2.log, stress-2.1-java-driver-2.2+PATCH.log,
> stress-2.1-java-driver-2.2.log, stress-2.2-java-driver-2.2+PATCH.log,
> stress-2.2-java-driver-2.2.log
>
>
> We are seeing some regression in performance when using cassandra-stress 2.2.
> You can see the difference at this url:
> http://riptano.github.io/cassandra_performance/graph_v5/graph.html?stats=stress_regression.json&metric=op_rate&operation=1_write&smoothing=1&show_aggregates=true&xmin=0&xmax=108.57&ymin=0&ymax=168147.1
> The cassandra version of the cluster doesn't seem to have any impact.
> //cc [~tjake] [~benedict]
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