Hi Doal
Thanks for posting here.
The current implementation does not have any support at the moment for
synchronization of the kind you are looking for. In fact its a very
simple share-all cache with last writer overwriting any previous writes.
It is also only tested to a limited extent to support lightweight cache
writes and is not suitable for high throughput writes. I admit our
focus has been a lot on the group composition and lifecycle correctness
and these aspects are only now beginning to be looked at.
That said, we are looking to significantly improve the Cache
functionality in the next Shoal rev (version 2.0 - Feb-March 2010
release timeframe) to provide on-demand caches with configurable
policies. We are at the requirement gathering stage at this point and
would welcome any inputs in this respect.
From your description, we would need to ensure message ordering
guarantees, configurable distributed locking at row, rowset or table
level, etc.
--Shreedhar
Doal Miller wrote:
>
> I have been looking at Shoal for some clustering functions for an
> upcoming project. The question I have is can a member synchronize the
> DSC so it is ensured that only one member is changing the cache at any
> given time.
>
>
>
> I thought I might be able to use fencing for this but I see that it
> doesn't stop changes to the DSC, and is specifically for node recovery.
>
>
>
> Is there some way to synchronize changes to the DSC or do you have any
> ideas?
>
>
>
> I appreciate your help, thanks,
>
> Doal Miller
>
> doal.miller_at_mir3.com
>
>
>