On 11 May 2011, at 15:53, Sanne Grinovero wrote: > 2011/5/11 Mircea Markus <mircea.mar...@jboss.com>: >> On 11 May 2011, at 13:29, Sanne Grinovero wrote: >>> First thing I thought when reading your email was "OMG do we support >>> on-the-fly hash implementation changes? crazy!" >>> >>> That's obviously not the case, but if you name it as >>> @ConsistenHashChangeListene that's what I would think. >> good point :-) >> ConsistentHashMembershipChange perhaps? >>> >>> Wouldn't it be better to change the exact timing of the viewchange >>> event? I don't see why Infinispan users might be more interested in >>> knowing about the topology details according to the transport than >>> what they are about the actual Infinispan hashing topology - I would >>> expect that when I receive which notification the new view is already >>> installed and ready to go; actually I thought that was the case since >>> ever. >>> >>> What would be the use cases to get the notification *before* the new >>> hash is installed? >> @ViewChanged listener is a CacheManager listener, so it's independent of >> the caches in that are in use. It is possible for the CacheManager to wait >> for all its distributed caches to install the view first, and only then >> dispatch the @ViewChange event, >> Not sure that's a good idea in the general case, though. > > let's talk about use cases. As an application developer building > something cool on top of Infinispan, what's the point in receiving an > event about new nodes being joined, if they're not ready to be used? > I'd rather have you notify me when new nodes joined and I can actually > start using them; the rest is low-level detail that an application > shouldn't worry about - I think - but I'm ready to take it back if you > find an example for which that's not true. TBH I can't find a convincing-enough use case to write down :-) There is a small semantic (again theory!) difference between @ViewChanged and @NodeJoined (which is a really cool replacement-name for ConsistentHashMembershipChange btw). ViewChange happens sooner than NodeJoined. This can be a matter of nanos or even seconds (timeout is by default 10 secs) - depending on how long the state transfer takes. I'd love to see other opinions around this as well.
_______________________________________________ infinispan-dev mailing list infinispan-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/infinispan-dev
