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From: Jonathan Ellis <jbellis@gmail.com>
Date: Tue, 1 Dec 2009 20:18:02 -0600
Message-ID: <e06563880912011818h6c9acfd9r8b85de67964fa337@mail.gmail.com>
Subject: Re: Persistently increasing read latency
To: cassandra-user@incubator.apache.org
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On Tue, Dec 1, 2009 at 7:31 PM, Freeman, Tim <tim.freeman@hp.com> wrote:
> Looking at the Cassandra mbean's, the attributes of ROW-MUTATION-STAGE an=
d ROW-READ-STAGE and RESPONSE-STAGE are all =A0less than 10. =A0MINOR-COMPA=
CTION-POOL reports 1218 pending tasks.

That's probably the culprit right there.  Something is wrong if you
have 1200 pending compactions.

This is something that upgrading to trunk will help with right away
since we parallelize compactions there.

Another thing you can do is increase the memtable limits so you are
not flushing + compacting so often with your insert traffic.

-Jonathan