The Block Disk Cache stores cached values on disk. Like the Indexed Disk Cache, the Block Disk Cache keeps the keys in memory. The Block Disk Cache stores the values in a group of fixed size blocks, whereas the Indexed Disk Cache writes items to disk in one chunk.
The Block Disk Cache has advantages over the normal indexed model for regions where the size of the items varies. Since all the blocks are the same size, the recycle bin is very simple. It is just a list of block numbers. Also, the Block Disk Cache will never need to be optimized. Once the maximum number of keys is reached, blocks will be reused.
############################################################## ##### DEFAULT REGION ######################################## jcs.default=blockDiskCache jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes jcs.default.cacheattributes.MaxObjects=0 jcs.default.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache ############################################################## ##### AUXILIARY CACHES ###################################### # Block Disk Cache jcs.auxiliary.blockDiskCache=org.apache.jcs.auxiliary.disk.block.BlockDiskCacheFactory jcs.auxiliary.blockDiskCache.attributes=org.apache.jcs.auxiliary.disk.block.BlockDiskCacheAttributes jcs.auxiliary.blockDiskCache.attributes.DiskPath=target/test-sandbox/block-disk-cache-huge jcs.auxiliary.blockDiskCache.attributes.MaxPurgatorySize=300000 jcs.auxiliary.blockDiskCache.attributes.MaxKeySize=1000000 jcs.auxiliary.blockDiskCache.attributes.blockSizeBytes=500 jcs.auxiliary.blockDiskCache.attributes.EventQueueType=SINGLE #jcs.auxiliary.blockDiskCache.attributes.EventQueuePoolName=disk_cache_event_queue ############################################################## ################## THREAD POOL CONFIGURATION ################# # Default thread pool config thread_pool.default.boundarySize=2000 thread_pool.default.maximumPoolSize=150 thread_pool.default.minimumPoolSize=4 thread_pool.default.keepAliveTime=350000 #RUN ABORT WAIT BLOCK DISCARDOLDEST thread_pool.default.whenBlockedPolicy=RUN thread_pool.default.startUpSize=4 # Disk Cache pool thread_pool.disk_cache_event_queue.useBoundary=false thread_pool.disk_cache_event_queue.minimumPoolSize=2 thread_pool.disk_cache_event_queue.keepAliveTime=3500 thread_pool.disk_cache_event_queue.startUpSize=10