I'd like something similar. If I have equal keys on two machines (given an orthogonal setup and a TACH), I'd like to suppress state transfer and run with only one copy until I can recover my machines. The business case is that in a degraded scenario, additional replicas aren't going to buy me anything, as a failure will most likely be at the machine level and will cause me to lose data. Once I've recovered the other machine, I can turn back on state transfer to get my data redundancy.
Erik -----Original Message----- From: infinispan-dev-boun...@lists.jboss.org [mailto:infinispan-dev-boun...@lists.jboss.org] On Behalf Of Mircea Markus Sent: Tuesday, June 04, 2013 5:44 AM To: infinispan -Dev List Subject: Re: [infinispan-dev] Suppressing state transfer via JMX Manik, what's wrong with Dan's suggestion with clearing the cache before shutdown? On 31 May 2013, at 14:20, Manik Surtani <msurt...@redhat.com> wrote: >> >> If we only want to deal with full cluster shutdown, then I think stopping all application requests, calling Cache.clear() on one node, and then shutting down all the nodes should be simpler. On start, assuming no cache store, the caches will start empty, so starting all the nodes at once and only allowing application requests when they've all joined should also work without extra work. >> >> If we only want to stop a part of the cluster, suppressing rebalancing would be better, because we wouldn't lose all the data. But we'd still lose the keys whose owners are all among the nodes we want to stop. I've discussed this with Adrian, and we think if we want to stop a part of the cluster without losing data we need a JMX operation on the coordinator that will "atomically" remove a set of nodes from the CH. After the operation completes, the user will know it's safe to stop those nodes without losing data. > > I think the no-data-loss option is bigger scope, perhaps part of ISPN-1394. And that's not what I am asking about. > >> When it comes to starting a part of the cluster, a "pause rebalancing" option would probably be better - but again, on the coordinator, not on each joining node. And clearly, if more than numOwner nodes leave while rebalancing is suspended, data will be lost. > > Yup. This sort of option would only be used where data loss isn't an issue (such as a distributed cache). Where data loss is an issue, we'd need more control - ISPN-1394. > Cheers, -- Mircea Markus Infinispan lead (www.infinispan.org) _______________________________________________ infinispan-dev mailing list infinispan-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/infinispan-dev _______________________________________________ infinispan-dev mailing list infinispan-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/infinispan-dev