Re: [infinispan-dev] cache loader/preload

Btw how do we deal with preloading in a cluster?

Eg how do we prevent every node from preloading the same data?

On Aug 14, 2013, at 16:09, Mircea Markus <mmarkus(a)redhat.com&gt; wrote: > > On 14 Aug 2013, at 20:53, Sanne Grinovero <sanne(a)infinispan.org&gt; wrote: > >> On 14 August 2013 17:59, Mircea Markus <mmarkus(a)redhat.com&gt; wrote: >>> >>> On 14 Aug 2013, at 15:26, Sanne Grinovero <sanne(a)infinispan.org&gt; wrote: >>> >>>> On 14 August 2013 11:15, Mircea Markus <mmarkus(a)redhat.com&gt; wrote: >>>>> Currently the "preload" attribute is configured at *loaders* level and the first cache loader in the chain is used for preloading. >>>>> A better place for preload might be the individual loader element: would indicate clearly which loader is used for preloading and also consistent with the fetchPeristentState which is again defined on a per loader basis. >>>>> >>>>> How does it sound? >>>> >>>> Very confusing actually :-) >>>> Are you going to prevent me to enable "preload" on multiple Cache >>>> Loaders elements? >>> >>> I'm not going to take anything from you, this is something you're not allowed to do ATM :-) >> >> That's exactly my point. I'm not allowed to do it ATM, but if you >> change the position of this attribute to *each* loader it will look >> like I could enable/disable it differently on a per-instance. > > Gotcha, I'll either add a check to allow specifying preload on a single store, or (if time allows) I'll implement the multiple preload feature. > >> >>> >>>> And what if I'm actually storing entries in >>>> different CacheStore instanced based on some discriminator, like the >>>> value (key) type? >>>> >>>> To make a practical example, the Lucene Directory CacheLoader only >>>> loads some specific types, and only from named indexes which match a >>>> configured name. You could want multiple instances using different >>>> configurations, so that for each index name stored in the same cache >>>> you actually store them in different cachestores. >>>> >>>> Similar situation, with the JPA CacheStore you might want to use >>>> multiple independent instances, one per mapped type. Not necessarily >>>> needed (one could improve the CacheStore implementation as well) but >>>> it gives lot of flexibility, like connecting to different RDBMs >>>> instances or with different credentials/schemas, etc... >>> >>> Indeed user might want this in the future. Moving "preload" at "loader" level would only facilitate that. >> >> Right. I'm making those examples to highlight the benefit of moving >> the attribute to each cachestore, as you proposed, but this only makes >> sense if you actually allow the option to be applied differently for >> each instance. > > Cheers, > -- > Mircea Markus > Infinispan lead (www.infinispan.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