[jbosscache-dev] CacheLoader preload with region based marshalling

[Brian Stansberry]

Manik Surtani wrote:
> 
> On 5 Jun 2008, at 13:39, Brian Stansberry wrote:
> 
>> The regions are created/registered after start(); i.e. after the point 
>> shown in the logs.  This is why I think it might just be a 
>> configuration mistake that's been in AS 5 all along; just wasn't 
>> exposed due to JBCACHE-1358. (In AS 4 there is no cacheloader involved.)
>>
>> Perhaps w/ region-based marshalling I shouln't use 
>> <preload>/</preload>. A nice fix to 
>> http://jira.jboss.com/jira/browse/JBCACHE-1009 would include logic to 
>> defer the preload until regions are activated.
> 
> Yes, agreed.  And this is not necessarily overly complex to do either:
> 
> When preloading stuff from cache loader:
> 1) Loop through all Fqns to be preloaded.
> 2) For each Fqn being preloaded, if any state is regionalised (i.e., a 
> non-null region) check if the region is activated.  If so, proceed as 
> normal, if not skip.
> 
> When a region is actvated:
> 1) Check if the region is a sub-region of any "preload" Fqns specified 
> in your cache loader cfg.
> 2) If so, attempt to preload that Fqn, but only for regions that match 
> the one being activated.  Skip others.
> 
> I wonder if it is worth fixing JBCACHE-1009 in 2.2.0.  It would warrant 
> another CR in 2.2.0 though.  Thoughts?  Votes on this?
> 

Per your comment on lazy loading being a virtue, I don't think I need 
this for AS 5. It's a nice idea though.

Re: another CR, probably should have one anyone so I can put it in the 
AS hudson runs for a couple days before it goes GA.  I can't put in a 
snapshot anymore -- illegal.

>> TBH, I don't see why I want <preload>/</preload> at all for this usage.
> 
> Yes - isn't lazy loading a virtue here anyway?  :-)
> 

Well, I like to just throw random stuff in my configs in order to 
exercise all the code paths. ;)

> And re: 2.1.1.GA, since JBCACHE-1358 is an obvious bug in JBC, I may 
> port this fix to 2.1.X which will cause future 2.1.X releases to break 
> in the same way.
> 
> Cheers
> Manik
> -- 
> Manik Surtani
> Lead, JBoss Cache
> manik at jboss.org
> 
> 
> 
> 
> 
> 

-- 
Brian Stansberry
Lead, AS Clustering
JBoss, a division of Red Hat
brian.stansberry at redhat.com