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

On 2/13/12 12:22 PM, Sanne Grinovero wrote: > I have two transactions, run in sequence: > - TX1 updates A > - TX2 deletes A > > If you send them both in async to the other datacenter, you'll have to > make sure they are not reordered. I know JGroups can provide that > guarantee, just wondering if it's the plan to do this via JGroups, or > if we have an own buffer that we can still guarantee the order, or > even better merge changes on the same keys like we do with the async CacheStore. This use case cannot be supported by option #3 AFAICS: the bridge between LON and SFO is completely asynchronous and doesn't know anything about sync or async RPCs, so TX2 can be applied in SFO before TX1. With option #2, if you run with SYNC, then the TX1 will complete before TX2 is started. Unless, of course, the 2 transactions are started on different nodes: then,  it depends on which TX acquires the locks first, but this is the same behavior as in a local cluster.