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From: Jonathan Ellis <jbellis@gmail.com>
Date: Wed, 7 Jul 2010 12:18:08 -0500
Message-ID: <AANLkTimoKpXwNIkPGkgtnGV0txveIFkqWCG7fXVTeorb@mail.gmail.com>
Subject: Re: Cluster performance degrades if any single node is slow
To: user@cassandra.apache.org
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On Wed, Jul 7, 2010 at 11:50 AM, Mason Hale <mason@onespot.com> wrote:
> I'm curious of what performance benefit is actually being gained from this
> optimization.

It's really pretty easy to saturate gigabit ethernet with a Cassandra
cluster.  Mulitplying traffic by roughly RF is definitely a lose.

> Sorry to keep beating this horse, but we're regularly being alerted to
> performance issues any time a mini-compaction occurs on any node in our
> cluster. I'm fishing for a quick and easy way to prevent this from
> happening.

I believe Brandon is in the process of suggesting enabling compaction
de-prioritization to Scott
(https://issues.apache.org/jira/browse/CASSANDRA-1181).

-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com