FetchStateOnStartup is a veeery useful thing in JbossCache but, as I understand, it replicates the whole stuff in the cache. Is there a way to make it replicate only a subset of nodes from the cache tree?
Here is why: we use cache a lot, in the run-time, and do quite a lot of "pre-caching" too. Servers pre-cache some stuff from the db, like: internationalized messages, country list, languages list, permission policies and some critical business entity objects, as well as slow and critical queries (under Hibernate). When server A starts up it pre-caches from the database, but when another server B starts up it should transfer the pre-cached information from A. This is for two reasons: 1) it's much faster for server B because pre-cache from database is not very fast (slow queries) 2) If B would begin pre-caching from the database and putting values in the cache, it would force A refresh its cache, right? Huge amount of unnecessary traffic would be created between A and B. FetchStateOnStartup is exactly the thing that provides with needed inital state replication but here is the problem - on the startup only the information that is part of the normal pre-cache should be replicated, not the whole runtime cache of servers in the cluster. The rest should be fetched by B, from A, one by one, only when an access request is made from the cache user, but not on the startup. This is very important because the amount of information that is usually pre-cache in our system is about 500megs, while runtime size of the cache is about 2 Gigs and can go all the way up to 4Gigs, right? I am worried about making server transfer several gigabytes of information over the network at startup. Using different caches for pre-cached and non-precached parts is not an option because both should be under Hibernate and Hibernate can not use two caches in parallel. We, also, have another requirement where we need to refresh information on a set of nodes. There are two problems with that, as I can see it: 1) There is no cluster-wide eviction in Jboss Cache, from what I read 2) After eviction only one server should re-cache from the database and forcingly push only this node's info to other members of the cache (which is kinda similiar task of selective state replication, right?) I am not sure if TreeCacheAOP can help with these, but I am afraid using AOP version is not an option because my folks really want the implementation to be J2EE-container independant :( thanks View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=3835760#3835760 Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=3835760 ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ JBoss-Development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
