I was accidentally sharing connections between threads, and getting strange results. Is your client multi threaded?

Can you provide some more information, such as the client library, how the data is written and  how you're deciding that the returned results are the wrong ones.

Is the read inconsistency against data that is frequently changing? Could it be a problem with the way the data is being stored?

Aaron




On 30 Jul, 2010,at 11:43 AM, Jianing Hu <jianing@gmail.com> wrote:

Hi Aaron,

Thanks for the reply. Can you explain what you mean by "sharing
connections around"?

I'm just calling a simple "get", and the data returned is for a
completely different key. It's intermittent and hard to produce in my
test environment, but can be observed in our production environment
couple hundred times a day.

Thanks,
- Jianing

On Thu, Jul 29, 2010 at 2:58 PM, Aaron Morton <aaron@thelastpickle.com> wrote:
> I noticed this once when accidentally sharing connections around. Could that
> be the case ?
>
> What sort of commands are you running ? Could you be seeing this problem ?
> http://www.mail-archive.com/user@cassandra.apache.org/msg04831.html
>
> Aaron
>
>
> On 29 Jul, 2010,at 12:47 PM, Jianing Hu <jianing@gmail.com> wrote:
>
> We recently migrated part of our MySQL database to a 3-node Cassandra
> cluster with a replication factor of 3. Couple of days ago we noticed
> that Cassandra sometimes returns the wrong data. Not corrupted data,
> but data for a different key than the one being asked for. This error
> appears to be random and intermittent, and happens for maybe every 10K
> reads. I'm working on a test suite that can reproduce this. Meanwhile
> just wanted to ask if anyone has seen this problem before? I've tried
> consistency levels of both QUORUM and ONE, and see the issue with
> both.
>
> Thanks,
> - Jianing
>