IBM 6.1.X manual com.ibm.wps.ac.PermissionCollectionCache, Portal Access Control Cache Hierarchy

Figure 1 shows the relationships among the various caches. The small cylinders represent cache instances. The green caches are caches of the portal user management (PUMA) component that are closely related to the caches of the portal access control component. The PUMA caches contain information originating from the user registry. Portal access control uses these caches for user identification and group membership retrieval.

The vertical axis represents the cache aggregation direction. The cache instances in layer N leverage cache instances of lower layers to compute their values. For example, when computing effective permissions (entitlements) for a user (cached in the ExplicitEntitlementsCache), the portal access control component leverages existing cache values from the ChildResourcesCache and RoleMappingCache.

Figure 1 Portal Access Control Cache Hierarchy

com.ibm.wps.ac.PermissionCollectionCache

Default size: 2000, default lifetime: 10240, usage pattern: regular (admit-threshold).

This cache contains permission collections that can be used for permission checks. It scales with the number of permissions in the system, i.e. the number of portal resources and permissions assigned on those. Entries in the cache typically are requested very frequently during permission checks. An admit-threshold is used to avoid caching rarely used permissions. You may wish to try different admit-threshold settings to tune this cache. Entries are never invalidated from the cache. Creating a cache entry is very fast since all required information is in-memory. A cache entry is small.

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W E BS P HE R E P O R T AL V 6 . 1 T U N I N G G U I D E