[infinispan-dev] X-datacentre replication: design suggestions

[Sanne Grinovero]

On 10 February 2012 19:17, Dan Berindei <dan.berindei at gmail.com> wrote:
> Mircea was saying that we'd only send over committed modifications, so
> no locking RPCs that need to be synchronous.

I understand the performance cost would be otherwise high, but is this
not defeating the purpose?
I would expect as a user that - if I need cross-datacenter replication
- I would get a strong guarantee that committed data is safe in both
locations, not that some might still need to be sent.
So I would expect that - for transactional operations only - the other
locations participate in the prepare phase.

If we go for async replication, won't we need as well some way to
guarantee that the other replicas apply changes in the correct order?

About the cons in #3, it states
"the state transfer needs to be customized to send all cluster's state
through the end-point."
Why? Can't we have each node connect directly? No endpoint -> no overloading.
If you think of it as an async cachestore, you would have each entry
managed by it's primary owner and possibly sent directly to the right
target (assuming routers and VPNs are transparent to our logic).