> We could extend the policy for craches as well, by adding a > minNumOwners setting and only triggering an automatic rehash when > there is a segment on the hash wheel with <= minNumOwners owners.
minNumOwners should be at least 1, which in the default use case (numOwners==2) would mean that we react to every leave. Whilst this functinality is very nice, I don't think it should have a high prio as most of the use cases I'm aware of use numOwners=2. > > We would have a properly installed CH, that guarantees at some point > in the past each key had numOwners owners, and a filter on top of it > that removes any leavers from the result of DM.locate(), > DM.getPrimaryLocation() etc. > > It would probably undo our recent optimizations around locate and > getPrimaryLocation, so it's slowing the normal case (without any > leavers) in order to make the exceptional case (organized shutdown or > a part of the cluster) faster. > The question is how big the cluster > has > to get before the exceptional case becomes common enough that it's > worth optimizing for... re:partial shutdown, due to consistency constraints, it won't be posible to controlled shutdow more than numOwners-1 nodes at any time, so not sure it this optimisation has a broad scope. For total shutdown, I guess we can use other means that rehash, e.g. a specific command that would disable it and start flushing to the store. _______________________________________________ infinispan-dev mailing list [email protected] https://lists.jboss.org/mailman/listinfo/infinispan-dev
