Implementation Guide › Performance Tuning › Web Tier Performance › Reduce Traffic between Your Web Agents and the Policy Server › Resource Cache

Resource Cache

Each Web Agent uses a resource cache to store the following information it receives from the Policy Server temporarily:

• Whether a resource is protected
• Any additional response attributes included in the policy

The Web Agent searches the resource cache to determine if a resource is protected before contacting the Policy Server. If the resource exists in the cache, traffic to the Policy Server is reduced because the Web Agent does not make an IsProtected call to the Policy Server.

Two Web Agent configuration parameters affect the resource cache. Consider the following as you plan your SiteMinder deployment:

• Resource Cache Timeout

  We recommend basing the timeout interval of the Web Agent resource cache on the results of your capacity planning tests. A timeout interval that is too small limits the effectiveness of the resource cache. The value of the ResourceCacheTimeout parameter in your Web Agent configuration determines the timeout interval of the resource cache.

• Resource Cache Size

  We recommend using a resource cache that is 10 percent larger than the largest number of URIs that you expect users to request. If you are protecting an application that uses dynamic URLs (such as URLs with query strings) consider using the IgnoreQueryData parameter instead of adjusting the size of the resource cache. The value of the MaxResourceCacheSize Web Agent configuration parameter determines the size of the resource cache.

Note: For more information, see the Web Agent Configuration Guide.