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WEBSPHERE PORTAL V6.1 TUNING GUIDE
corresponding entitlements are not already cached. Entries are invalidated from this
cache during role mapping creation, role mapping deletion, resource deletion,
externalization, internalization, and logout of the user. Creating a cache entry means
executing at least one, but potentially multiple database queries. An entry in the cache is
relatively small.
com.ibm.wps.ac.ExplicitEntitlementsCache.* and
com.ibm.wps.ac.ChildEntitlementsCache
Default size: 10000, default lifetime: varying (around 10000), usage pattern: invalidation
checking.
These caches contain the permissions of a user or group on a number of resources of
the same ResourceType. There are dedicated caches for the different ResourceTypes.
For example, the cache for pages is called com.ibm.wps.ac.
ExplicitEntitlementsCache.CONTENT_NODE. All ResourceTypes that are not
specified explicitly will be cached in the default cache. The size of this cache scales with
the number of active users/groups multiplied by the different ResourceTypes valid for
this cache and accessed by the users and groups, either by ‘using’ the resource during
navigating the portal or by portal administration. There is one entry per set of
permissions per WebSphere Portal domain. Entries are read during ‘regular’ access
control requests, during page rendering and, especially, during portal administration. If a
certain resource type is not used, you will see only misses and no other activity on the
corresponding cache. Entries are invalidated from this cache during all access control
modifications and logins. Creating an entry in one of these caches typically can be done
from in-memory information in the lower-level caches. If the required information is not
available multiple database requests might be required to create a cache entry. An entry
into the cache is rather small, but built of multiple objects typically stored in other caches.
com.ibm.wps.ac.ExternalOIDCache
Default size: 10000, default lifetime: 8640, usage pattern: regular.
This cache contains the mapping between the external ObjectIDs of individual protected
resources, for example page or portlet IDs, and the portal access control specific
ObjectIDs stored in the database table PROT_RES. Entries are read from the cache
during many portal access control requests. The size of this cache scales with the
number of protected resources accessed by the active users in the system. Since this
mapping is immutable, this cache is never explicitly invalidated. Creating a cache entry
requires a single row database query. An entry in the cache is fairly small.
com.ibm.wps.ac.groupmanagement.NestedGroupCache /
com.ibm.wps.ac.groupmanagement.GroupCache
Default size: 1000, default lifetime: 3600, usage pattern: regular.
Only one of these two caches is used in a WebSphere Portal installation depending on
your ‘nested groups’ setting. If nested groups are supported, the NestedGroupCache
cache will be used, otherwise the GroupCache is used. The caches contain the nested
