10.4.2 Enabling dynamic cache service
The dynamic cache service is an in-memory cache system that has disk offload capability. Its caching behavior is defined in an XML file named cachespec.xml. A GUI tool for building the cache policy file is available, we describe it in detail in 10.3.2, Dynamic Cache Policy Editor.
Unique ID strings distinguish unique entries in WAS's dynamic content caching solution. These ID strings can be defined...
- declaratively with cachespec.xml
- programmatically by the user's Java program
WAS dynamic cache service can control external caches. Different groups of external caches can be defined, each with its own set of member caches. The interface between WAS and the external cache is the External Cache Adapter provided by WAS. We elaborate more on this topic in WebSphere external caching scenarios.
The dynamic cache service includes an alternative feature named disk offload, which stores the overflow cache entries on disk for potential future access. This feature removes the dynamic cache memory constraints experienced in older WAS versions (this was already available in WebSphere V5).
To enable dynamic caching for an appserver...
- Open WAS console.
- Click Servers -> Application servers in the navigation tree.
- Select your appserver.
- In the Container Settings pane, select Container Services -> Dynamic Cache Service.
- Select Enable service at server startup in the Startup state field. This setting should be enabled by default.
- Click Apply or OK.
All changes made to the dynamic cache service properties take effect after restarting the server.
The configuration panel of the dynamic cache service in the Administrative Console allows you to configure the disk offload (see Configure disk offload) and cache replication options. We discuss cache replication in 10.5.4, Cache replication.
