On 12 Apr 2010, at 14:08, Mircea Markus wrote:
> Another way to do it is by specifying an associator (not my idea TBH [1]).
> This is non-intrusive and no-api changes as well.
Is it non-intrusive? Doesn't this mean that keys need to implement an interface?
[1] describes two approaches. 1st (KeyAssociation) is the intrusive one (corresponds
you 1) ). The second approach discussed in [1] is based on an KeyAssociator and is
non-intrusive.
> Cheers.
> Mircea
>
> [1]
http://coherence.oracle.com/display/COH35UG/Data+Affinity
>
> On 12 Apr 2010, at 15:36, Manik Surtani wrote:
>
>> Re: subject (see
https://jira.jboss.org/jira/browse/ISPN-359), there are a couple
of approaches that could be taken:
>>
>> 1. Don't use key.hashcode() as the seed in determining to which nodes an
entry is mapped, but instead on a well-known method or annotated method (e.g., int
getGroupID() or a method annotated with @GroupId). The way I see it, this approach has:
>>
>> + Will work, no additional overheads of AtomicMaps
>> - Cost (reflection)
>> - Intrusive (what if users have no control over the key class, e.g., String
keys?)
>>
>> 2. Additional API methods on the cache - cache.put(K, V, G), cache.putAll(Map,
G), etc.
>>
>> + Non-intrusive
>> - Overhead of AtomicMaps + additional entries for mappings
>> + or - (depending on how you look at it) all keys in the group will be locked
together, etc, a side-effect of using AtomicMaps
>>
>> My pref is for approach #2. In terms of implementation, here is what I have in
mind:
>>
>> * A GroupingInterceptor that intercepts the call early on if the call is a put(K,
V, G) or something similar.
>> * Breaks up the call to a put(K, G) and a getAtomicMap(G).put(K, V). Wrapped in
a tx to ensure atomicity.
>> * get(K), etc intercepted as well, replaced with getAtomicMap(get(K)).get(K)
>> * remove(K), etc intercepted with getAtomicMap(get(K)).remove(K)
>>
>> One of the issues with the API approach is that it heavily pollutes the Cache
API. It will double the number of put() methods on Cache (currently 18 variants of put,
including ones that take in lifespans and maxIdles, async versions that return futures,
etc.) Perhaps this could be in an additional sub-interface interface? GroupedCache? Or
is this degree of method overloading not too confusing?
>>
>> Cheers,
>> --
>> Manik Surtani
>> manik(a)jboss.org
>> Lead, Infinispan
>> Lead, JBoss Cache
>>
http://www.infinispan.org
>>
http://www.jbosscache.org
>>
>>
>>
>>
>> _______________________________________________
>> infinispan-dev mailing list
>> infinispan-dev(a)lists.jboss.org
>>
https://lists.jboss.org/mailman/listinfo/infinispan-dev
>
> _______________________________________________
> infinispan-dev mailing list
> infinispan-dev(a)lists.jboss.org
>
https://lists.jboss.org/mailman/listinfo/infinispan-dev
--
Manik Surtani
manik(a)jboss.org
Lead, Infinispan
Lead, JBoss Cache
http://www.infinispan.org
http://www.jbosscache.org
_______________________________________________
infinispan-dev mailing list
infinispan-dev(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/infinispan-dev