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From Hugo <h...@unitedgames.com>
Subject Re: Question on Eventual Consistency
Date Mon, 19 Jul 2010 19:34:27 GMT
I'm using CL=QUORUM (=Hector default) for both reads and writes. Most of 
the times, the test passes, but sometimes it fails because I get back 
the old value. Since the test is single-threaded, I guess it is a bug. 
I'll try to reduce the test to something smaller that can be used for 
troubleshooting.

By the way, is it documented somewhere under what circumstances one can 
expect inconsistencies and when not?

On 7/19/2010 9:26 PM, Ran Tavory wrote:
> if your test case is correct then it sounds like a bug to me. With one 
> node, unless you're writing with CL=0 you should get full consistency.
>
> On Mon, Jul 19, 2010 at 10:14 PM, Hugo <hugo@unitedgames.com 
> <mailto:hugo@unitedgames.com>> wrote:
>
>     Hi,
>
>     Being fairly new to Cassandra I have a question on the eventual
>     consistency. I'm currently performing experiments with a
>     single-node Cassandra system and a single client. In some of my
>     tests I perform an update to an existing subcolumn in a row and
>     subsequently read it back from the same thread. More often than
>     not I get back the value I've written (and expected), but
>     sometimes it can occur that I get back the old value of the
>     subcolumn. Is this a bug or does it fall into the eventual
>     consistency?
>
>     I'm using Hector 0.6.0-14 on Cassandra 0.6.3 on a single disk,
>     double-core Windows machine with a Sun 1.6 JVM. All reads and
>     writes are quorum (the default), but I don't think this matters in
>     my setup.
>
>     Groets, Hugo.
>
>

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