On 17 Oct 2011, at 09:13, Dan Berindei wrote:

On Fri, Oct 14, 2011 at 9:29 PM, Vladimir Blagojevic
<vblagoje@redhat.com> wrote:
After Mircea's thorough review and advice from him and Sanne we are
almost ready to integrate FineGrainedAtomicMap. I say almost because
Sanne, Mircea and I concluded that two questions remain unanswered.

1) Should we stick fine-grained functionality under current AtomicMap
and discard legacy AtomicMap? FineGrainedAtomicMap seems to offer a
super-set of AtomicMap features and we should not confuse users with yet
another AtomicMap; at the same time we have less headache maintaining
AtomicMap codebase.

How's the performance of the fine grained AtomicMap compared to the old one?
If the performance is identical then I see no reason to keep the old
one around, otherwise we already have problems keeping up with the
performance of JBossCache 1.4 (see
http://community.jboss.org/message/630238) so I would keep the old one
around.

+1. A simple test that does puts would tell us that straight away.

If we choose to allow both fine grained(FGAM) and non-faine grained maps(AM), then we also need to be concerned with the following transactional aspect: what happens if tx1 access key "k" using a FGAM and tx access same "k" using an AM. Perhaps not allow that kind of mixed access for now?

2) This one is a bit technical. What should we do if tx1 deletes entire
AtomicMap while tx2 updates entries in the same Map. Should we create a
new Map and apply deltas to a new fresh map *or* simply discard delta
changes because entire Map has been deleted?

I would say not simply discard the changes, but throw an exception and
roll back tx2 as well.

That would work. Also if a FGAM method is called and that FGAM has been deleted/replaced then the FGAM method should throw an exception.

Cheers
Dan
_______________________________________________
infinispan-dev mailing list
infinispan-dev@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/infinispan-dev