Setting eviction policies dinamically
sancheski May 5, 2008 1:09 PMHi guys,
I am trying to configure different eviction policies to different regions dinamically and I am facing some problems.
This is what I want:
Create an eviction policy in /NODE
Create an evcition policy in /NODE/SUBNODE_1
Create an eviction policy in /NODE/SUBNODE_2 and so on
Even create an eviction policy in /NODE/SUBNODE_1/SUBNODE_A and so on
I expected that I could create them dinamically as I am able to create them using the tree cache config file, but I have encountered some problems.
First of all, if I try to create a new eviction for, let's say /NODE/SUBNODE_1, and /NODE already had one, it throws a
RegionNameConflictException because at the time of creating the new Region (/NODE/SUBNODE_1) it checks for region conflicts. As I see in the source code, it will never allow to create a new Region under an existing one. Should work that way?
Secondly, I tried to remove any parent region of a given one from the RegionManager to avoid conlflicts from first point, and then configure all eviction policies bottom-up. That is, following last example, first I set an evcition policy to /NODE/SUBNODE_1 and then to /NODE.
In this case, it seems that everything is configured fine, but only the eviction policy configured for every subnode is working. As I see, there are no node entries in the eviction queue for the parent region, check it out yourself below:
/NODE/ class org.jboss.cache.eviction.FIFOConfiguration LFUConfiguration: maxNodes = 2 Nodes in eviction queue: 0 /NODE/SUBNODE_1 class org.jboss.cache.eviction.FIFOConfiguration LFUConfiguration: maxNodes = 5 Nodes in eviction queue: 2
This is, mainly, how I set the eviction policies:
public final void addEvictionPolicy(EvictionPolicy evictionPolicy, String fqn) { // Activate eviction Policies RegionManager regionMgr = getUnderlyingTreeCache().getEvictionRegionManager(); // get EvictionConfiguration EvictionConfiguration config = getEvictionConfiguration(evictionPolicy); if (regionMgr.hasRegion(fqn)) { Region region = regionMgr.getRegion(fqn); region.setEvictionConfiguration(config); logger.debug("Region[{}] configured with {}", fqn, somEvictionPolicy); } else { EvictionPolicy policy = getEvictionPolicy(evictionPolicy); policy.configure(getUnderlyingTreeCache()); try { regionMgr.createRegion(fqn, policy, config); } catch (RegionNameConflictException e) { logger.error("Region Name conflict", e); } logger.debug( "Region[{}] does not exist in RegionManager. Created and configured with {}", fqn, evictionPolicy); } }
Hope someone have any idea of how to set dinamically an eviction policy over a region that already its own parent region has one set. By the way, I am using JbossCache 1.4.1.SP8 and JbossAS-4.2.2
I think this is a normal case that it could come up in a real application, so I think that someone who already had at any time encountered this requirement could help me.
Thanks in advance!