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Commons JCS™

JDBC Disk Auxiliary Cache Configuration

The following properties apply to the JDBC Disk Cache plugin.

JDBC Disk Configuration Properties

Property Description Required Default Value
MaxPurgatorySize The maximum number of items allowed in the queue of items to be written to disk. N 5000
url The database url. The database name will be added to this value to create the full database url. Y
database This is appended to the url. Y
driverClassName The class name of the driver to talk to your database. Y
tableName The name of the table. N JCS_STORE
testBeforeInsert Should the disk cache do a select before trying to insert new element on update, or should it try to insert and handle the error. N true
maxActive This sets the maximum number of connections allowed. Y
allowRemoveAll Should the disk cache honor remove all (i.e. clear) requests. You might set this to false to prevent someone from accidentally clearing out an entire database. N true
UseDiskShrinker Should the disk cache try to delete expired items from the database. N true
ShrinkerIntervalSeconds How often should the disk shrinker run. N 300

Example Configuration

					
##############################################################
################## AUXILIARY CACHES AVAILABLE ################
# JDBC disk cache
jcs.auxiliary.JDBC=org.apache.commons.jcs.auxiliary.disk.jdbc.JDBCDiskCacheFactory
jcs.auxiliary.JDBC.attributes=org.apache.commons.jcs.auxiliary.disk.jdbc.JDBCDiskCacheAttributes
jcs.auxiliary.JDBC.attributes.userName=sa
jcs.auxiliary.JDBC.attributes.password=
jcs.auxiliary.JDBC.attributes.url=jdbc:hsqldb:
jcs.auxiliary.JDBC.attributes.database=target/cache_hsql_db
jcs.auxiliary.JDBC.attributes.driverClassName=org.hsqldb.jdbcDriver
jcs.auxiliary.JDBC.attributes.tableName=JCS_STORE2
jcs.auxiliary.JDBC.attributes.testBeforeInsert=false
jcs.auxiliary.JDBC.attributes.maxActive=15
jcs.auxiliary.JDBC.attributes.allowRemoveAll=true
jcs.auxiliary.JDBC.attributes.MaxPurgatorySize=10000000
jcs.auxiliary.JDBC.attributes.UseDiskShrinker=true
jcs.auxiliary.JDBC.attributes.ShrinkerIntervalSeconds=300
        
				

JDBC Disk Event Queue Configuration

Property Description Required Default Value
EventQueueType This should be either SINGLE or POOLED. By default the single style pool is used. The single style pool uses a single thread per event queue. That thread is killed whenever the queue is inactive for 30 seconds. Since the disk cache uses an event queue for every region, if you have many regions and they are all active, you will be using many threads. To limit the number of threads, you can configure the disk cache to use the pooled event queue. Using more threads than regions will not add any benefit for the indexed disk cache, since only one thread can read or write at a time for a single region. N SINGLE
EventQueuePoolName This is the name of the pool to use. It is required if you choose the POOLED event queue type, otherwise it is ignored. Y n/a

Example Configuration Using Thread Pool

					
##############################################################
################## AUXILIARY CACHES AVAILABLE ################
# JDBC disk cache
jcs.auxiliary.JDBC=org.apache.commons.jcs.auxiliary.disk.jdbc.JDBCDiskCacheFactory
jcs.auxiliary.JDBC.attributes=org.apache.commons.jcs.auxiliary.disk.jdbc.JDBCDiskCacheAttributes
jcs.auxiliary.JDBC.attributes.userName=sa
jcs.auxiliary.JDBC.attributes.password=
jcs.auxiliary.JDBC.attributes.url=jdbc:hsqldb:
jcs.auxiliary.JDBC.attributes.database=target/cache_hsql_db
jcs.auxiliary.JDBC.attributes.driverClassName=org.hsqldb.jdbcDriver
jcs.auxiliary.JDBC.attributes.tableName=JCS_STORE2
jcs.auxiliary.JDBC.attributes.testBeforeInsert=false
jcs.auxiliary.JDBC.attributes.maxActive=15
jcs.auxiliary.JDBC.attributes.allowRemoveAll=true
jcs.auxiliary.JDBC.attributes.MaxPurgatorySize=10000000
jcs.auxiliary.JDBC.attributes.UseDiskShrinker=true
jcs.auxiliary.JDBC.attributes.ShrinkerIntervalSeconds=300
jcs.auxiliary.JDBC.attributes.EventQueueType=POOLED
jcs.auxiliary.JDBC.attributes.EventQueuePoolName=disk_cache_event_queueue

##############################################################
################## OPTIONAL THREAD POOL CONFIGURATION #########
# Disk Cache pool
thread_pool.disk_cache_event_queue.useBoundary=false
thread_pool.disk_cache_event_queue.boundarySize=500
thread_pool.disk_cache_event_queue.maximumPoolSize=15
thread_pool.disk_cache_event_queue.minimumPoolSize=10
thread_pool.disk_cache_event_queue.keepAliveTime=3500
thread_pool.disk_cache_event_queue.whenBlockedPolicy=RUN
thread_pool.disk_cache_event_queue.startUpSize=10