Least recently used. A MRU (Most recently used) does exist, but I doubt that this is what you want.
Al On 4/26/06, Eddie Liu <[EMAIL PROTECTED]> wrote: > > Thanks for the explanation! I now have a much clearer picture of how JCS > works. > > One thing I want to make sure I understand correctly: When I am using LRU > memory cache, the *last* recently used item will be spooled to disk when > an > item is put into memory? Or the *least* recently used item will be > spooled > to disk? > > Thanks. > > Eddie > > > On 4/24/06, Aaron Smuts <[EMAIL PROTECTED]> wrote: > > > > The memory shrinker does 2 things. > > > > (1) It removes items that have exceeded their max > > life. That is, it removes them altogether. It > > doesn't put them on disk; it simply gets rid of them. > > If you don't run the memory shrinker these items can > > hang around in memory, but they will not be returned > > by the jcs.get call. Each time you get an item from > > the cache, JCS checks to see if it has expired. If it > > has expired, it will not be returned. > > > > (2) The memory shrinker moves items from memory to > > disk if the items have exceeded their max memory time. > > In you cache.ccf file this is set on the line that > > looks like this: > > jcs.region.listDS.cacheattributes.MaxMemoryIdleTimeSeconds=5 > > You have it set to a mere 5 seconds. This is why the > > items are being put to disk so quickly. Remember that > > items are also put to disk when the max memory size. > > If you are using the LRU memory cache, which is the > > defualt, the lest recently used item will be spooled > > to disk when an item is put into memory. Items are > > put into memory in three ways: (a) An item goes into > > memory if you call put( key, value ). (b) Items are > > put into memory if they are retrieved from disk. (c) > > If an item is put into the cache from a lateral or > > remote auxiliary, it will be added to memory. > > > > I hope this helps. > > > > Cheers, > > > > Aaron > > > > --- Eddie Liu <[EMAIL PROTECTED]> wrote: > > > > > I might not understand enough, but when I enabled > > > MemoryShrinker, in the log > > > when it says: > > > > > > [4/24/06 17:17:16:688 EDT] 00000036 CacheEventQue I > > > Cache event queue > > > created: CacheEventQueue [listenerId=-842985658, > > > cacheName=enforce2ListDS] > > > [4/24/06 17:17:26:703 EDT] 00000041 CacheEventQue I > > > QProcessor exiting for > > > CacheEventQueue [listenerId=-842985658, > > > cacheName=enforce2ListDS] > > > > > > From my observation, that was when it wrote to disk > > > cache? Right after I > > > saw that, I made another request for the same cached > > > data, but this time it > > > returned null on the jcs.get(id) call. > > > > > > Why it didn't load it from disk? I timed it and > > > made sure I made the new > > > request after it wrote to disk but BEFORE it exceed > > > the maxLifeSeconds. But > > > it behaved as if it has already expired. Is there > > > anything else I need to > > > do to get the data from disk-cache? > > > > > > Thanks alot! > > > > > > Eddie > > > > > > Configuration as follow: > > > > > > > > ----------------------------------------------------------------------------- > > > jcs.region.listDS=DC > > > > > > > > jcs.region.listDS.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes > > > jcs.region.listDS.cacheattributes.MaxObjects=1200 > > > > > > > > jcs.region.listDS.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache > > > jcs.region.listDS.elementattributes.IsEternal=false > > > > > jcs.region.listDS.elementattributes.MaxLifeSeconds=30 > > > jcs.region.listDS.elementattributes.IdleTime=1800 > > > jcs.region.listDS.elementattributes.IsSpool=true > > > jcs.region.listDS.elementattributes.IsRemote=true > > > jcs.region.listDS.elementattributes.IsLateral=true > > > > > jcs.region.listDS.cacheattributes.UseMemoryShrinker=true > > > > > jcs.region.listDS.cacheattributes.MaxMemoryIdleTimeSeconds=5 > > > > > jcs.region.listDS.cacheattributes.ShrinkerIntervalSeconds=5 > > > jcs.region.listDS.cacheattributes.MaxSpoolPerRun=500 > > > > > > > > ----------------------------------------------------------------------------- > > > > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > >
