uPortal contains a number of configurable caches that you may wish to tune to improve performance. Caches are tuned via the ehcache.xml file in uportal-impl/src/main/resources/properties/ehcache.xml. This file contains hints about how to best tune the cache to match your expected number of portlets, sessions, etc. For example:
<!--
| Caches PortletPreferencesImpl's list of preference objects
| - 1 x subscribed portlet x user
| - 1 x published portlet
| - replicated by invalidation
+-->
<cache name="org.jasig.portal.portlet.dao.jpa.PortletPreferencesImpl.portletPreferences"
eternal="false" maxElementsInMemory="15500" overflowToDisk="false" diskPersistent="false"
timeToIdleSeconds="900" timeToLiveSeconds="1800" memoryStoreEvictionPolicy="LRU" statistics="true" />
After making any changes to this source file, please run an "ant deploy-war" and restart the portal.