dotCMS - Open Source Content Management System, Ondemand CMS, and Professional Support

Configuring the dotCMS Cache

The basic Config of the dotCMS cache system with the release of 1.6.5 has become really simple.  If you edit the file common/ext-ejb/dotmarketing-config.properties and search for the property "INSTANCE_SIZE" you can set it to small, med, or large.  This property provides an easy way to configure the cache.  A med instance would be a JVM under 1.5 gig of memory. A large instance would be a JVM over 1.5 gigs.  The default value is small and is for machines only providing dotCMS with 512Megs of ram.

The above configuration is all that most will need but if you have a really large system or a system where you have enough ram to support a larger cache in memory you can configure the following files.

common/ext-ejb/cache-configuration-region-large.xml

common/ext-ejb/cache-configuration-region-med.xml

common/ext-ejb/cache-configuration-region-small.xml

Depending upon which size config you run you should edit the appropriate file.  The files control how many of each object can live in cache.  For example for content

<region name="ContentletCache" policyClass="org.jboss.cache.eviction.LRUPolicy">
     <attribute name="maxNodes">2000</attribute>
     <attribute name="minTimeToLiveSeconds">0</attribute>
     <attribute name="timeToLiveSeconds">0</attribute>
     <attribute name="maxAgeSeconds">0</attribute>
</region>

The maxNodes is saying that 2000 different pieces of content live in the cache before it flushes the least used.  You will find config like this for many of the objects that are cached inside of dotCMS.  There is a default with the name /_default_ which will be used for any object not specifically defined with its own region.