D A T A S T O R E
The datastore caches contain data read from the portal database. It is not the goal of these caches to be a complete image of the DB content, but to have
com.ibm.wps.datastore.services.Identification.OidAndUniqueName.cache
Default size: 5000, default lifetime: infinite, usage pattern: regular.
This cache stores unique names. It is used quite frequently during page rendering and especially administration of unique names. Page and portlet unique names make up the biggest part of the cache content. The cache should be large enough to hold entries for the most frequently used pages and portlets having a unique name associated with them. Note that not all resources have a unique name associated with them. To eliminate database lookups the cache size could correspond to the database table UNIQUE_NAME multiplied by two, to allow for mapping in two directions. Creating a cache entry involves reading one entry from the portal database. An entry object into the cache is fairly small.
com.ibm.wps.datastore.PortalIdCache.vpPerLpid.cache
Default size: 1000, default lifetime: infinite, usage pattern: regular.
This cache maps long Virtual Portal object IDs to the corresponding portal internal short ID. It scales with the number of virtual portals in the system, plus one additional entry. It is used heavily only if more than one virtual portal exists in the system. Data is read from the cache during every rendering request then. For optimal caching the size should be set to the number of Virtual Portals defined in the system. Creating a cache entry involves one
com.ibm.wps.datastore.PortalIdCache.explicitLpidPerVP
Default size: 100, default lifetime: infinite, usage pattern: regular.
This cache maps the short object ID for a virtual portal to the corresponding long ID. In comparison to cache com.ibm.wps.datastore.PortalIdCache.vpPerLpid.cache it stores the reverse mappings. Hence all other descriptions given above also apply here.
com.ibm.wps.datastore.pageinstance.OIDCache
Default size: 3000, default lifetime: infinite, usage pattern: regular.
This cache stores information on portal pages for fast retrieval during login or page navigation. It scales with the number of page instances in the system. It is one of the most frequently used caches and should be large enough to hold all pages that are frequently accessed by users. Pages are loaded and put into the cache by direct navigation, creating a link to another page or by working with the page during portal administration (always including all higher derivation levels). Creating a cache entry includes one
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