[infinispan-dev] abstracting key locating, asymmetric clusters

[Christian Kulenkampff]

Hi all,
I just want to share some thoughts on Infinispan. Probably you already
had similar ideas, maybe you can provide some keywords, so I can
search for discussions in the archive.

As I understand, the ConsistentHash works just as a consistent hash
based "locator" for keys in the cluster. Basically one could implement
full replication with a special ConsistentHash that always returns all
addresses in the cluster. A ConsistentHash/"locator" has to be uniform
over the entire cluster to make it work. In principle this is the only
requirement for a "locator".
Currently there is only one parameter for the "locator" - a set with
all nodes in the cluster. If there would be a way to pass (maybe
dynamically) more parameters to a "locator" in a consistent way, many
possibilities would open up: e.g. an asymmetric cache configuration by
feeding the locator with a distributed registry; switching hash
functions at runtime; subscribable keys; keys, that have to stay at a
special node... Also it may be possible to remove the replication mode
and instead provide a special locator. To make this work rebalancing
would have to be more fine grained. E.g. it should be possible for the
locator (or its manager?) to ignore a view change or to trigger some
rebalance work per cache.

What do you think about it?

Cheers,
Christian