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From Hugo <h...@unitedgames.com>
Subject Re: Consistency issue
Date Fri, 03 Sep 2010 13:35:06 GMT
  I'm using the Hector defaults, which are QUORUM for reads and writes.

On 9/3/2010 3:18 PM, Nick Telford wrote:
> Are you using QUORUM for both writes and reads?
>
> The behaviour you're seeing sounds like something I'd expect to see if 
> you used NONE for writes.
>
> On 3 September 2010 14:12, Hugo <hugo@unitedgames.com 
> <mailto:hugo@unitedgames.com>> wrote:
>
>     I'm using QUORUM, but in my single-node setup this doesn't matter
>     IMHO.
>
>
>     On 9/3/2010 1:51 PM, Nick Telford wrote:
>>     Which ConsistencyLevels did you use for your batchMutate() and
>>     getSlice() operations?
>>
>>     ConsistencyLevels directly dictate the level of consistency you
>>     will get with your data.
>>
>>     Regards,
>>
>>     Nick Telford
>>
>>     On 3 September 2010 12:03, Hugo <hugo@unitedgames.com
>>     <mailto:hugo@unitedgames.com>> wrote:
>>
>>          Hi,
>>
>>         I'm performing tests with Cassandra 0.6.5 with Hector
>>         0.6.0-14 on a single machine (one node cluster). I've noticed
>>         an issue with consistency.
>>
>>         In my tests I perform a KeySpace.batchMutate() to update a
>>         column and immediately after that I perform a
>>         KeySpace.getSlice() on the same column (from within the same
>>         thread). I noticed that occasionally I get back the previous
>>         value rather than the value I've just written.
>>
>>         My guess is that this occurs because Hector uses pooled
>>         connections and both my requests are executed on different
>>         connections. I suspect this causes a race condition in
>>         Cassandra between the getSlice() and the batchMutate().
>>
>>         Can anyone confirm my suspicions and does anyone have a
>>         solution for this?
>>
>>         Groets, Hugo.
>>
>>
>

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