[rabbitmq-discuss] Consumer group

[Tim Watson]

Hi

On 10 Oct 2012, at 18:28, kishore g wrote:

> Hi,
> 
> I am writing this email to get feedback about a rabbitmq consumer
> group. We developed this recipe using Helix, a generic cluster
> management system which we open sourced yesterday. In order to
> demonstrate the ease of developing applications with Helix, we chose
> to write a rabbitmq-consumer-group.
> 
> You can find more info about that here
> 
> https://github.com/linkedin/helix/wiki/Sample_App
> 
> It would be great if you can provide feedback about this app.
> 

This is very interesting, and the sample app seems pretty useful from a client's perspective in terms of recovering from failures especially. One thing I'm interested in understanding is what you would do (in general) with stale values in the case where a network partition has occurred and the leader happened to wind up in the non-quorum island, which I believe is legal in zookeeper so long as you've not overwritten the value yourself. I'm very interested to see what approach can be applied when that happens, as it's a pain having to handle this kind of thing when dealing with consensus protocols. Also do you rely on zookeeper itself to resolve any conflicts when a partitioned cluster comes back together, or is there something in Helix that's handling it - or do the clients get to cooperate to resolve conflicts and if so how? 

Anyway, looks like a very interesting piece of kit. :)

Cheers,
Tim