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From: Wouter de Bie <wouter.de.bie@deltaprojects.se>
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Subject: Consitency level ONE
Date: Tue, 29 Jun 2010 11:54:07 +0200
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To: user@cassandra.apache.org
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Hi all,

I'm having some issues with read consistency level ONE. The Wiki (and =
other sources) say the following:

Will return the record returned by the first node to respond. A =
consistency check is always done in a background thread to fix any =
consistency issues when ConsistencyLevel.ONE is used. This means =
subsequent calls will have correct data even if the initial read gets an =
older value. (This is called read repair.)

However, when looking at the code, it seems that the read is only =
directed towards the first node that is suitable (and alive). This means =
that a slow node will cause slow responses even though my replication =
factor is > 1. I would expect the read to go to all the suitable nodes =
and as soon as one of those nodes responds, the reply is used (just as =
the documentation says).

Moving to Quorum reads would solve part of this problem, but with one =
server down and 1 slow one, I'm back to square one.=20

Greetings,

Wouter