Setting Windchill Cache Property Values
The assistant sets cache settings in Windchill application properties. The first set of properties it considers are those that size in-memory data caches.
Optimal cache tuning is difficult unless the system is under load. The Windchill Configuration Assistant simply suggests initial cache sizes based on the number of rows it finds in specific tables in the database.
The following Windchill cache properties are configured:
wt.admin.cache.maxDomains
wt.cache.size.AclCache
wt.cache.size.EnumerationDefinitionCache
wt.cache.size.IBADefViewManager$IBADefViewCache
wt.cache.size.IndexListCache
wt.cache.size.PagingSessionCache
wt.cache.size.PolicyAcl
wt.cache.size.PreferenceCache
wt.cache.size.RoleAccessCache
wt.cache.size.SessionCache
wt.cache.size.StandardFederatedServerHelper$RemoteObjectIdCache
wt.cache.size.StandardFvService$ActiveFolderCache
wt.cache.size.StandardUfidSrvService$RemoteObjectIdCache
wt.cache.size.StructEnumAttTemplateCache
wt.cache.size.TypeDefinitionCache2
wt.cache.size.WTPrincipalCache
wt.services/rsc/default/ObjectReferenceCacheTable/ContainerCache.Size
wt.services/src/default/ObjectReferenceCacheTable/ContainerTeamCache
Each cache comprises multiple entries, where each entry effectively represents one row in the corresponding database table. Windchill caches should be sized to maintain only recently accessed data rows (also known as the “working set”).
The assistant uses two basic algorithms to calculate cache sizes. The first cache sizing algorithm obtains the total number of rows in a database table and sizes the cache based on a configurable percentage of the table row count total.
The configurable percentages are defined using the following properties in Configurator.properties:
WTContainer.cache.percent
ContainerTeam.cache.percent
WTPrincipal.cache.percent
PolicyAcl.cache.percent
RemoteObjectInfo.cache.percent
AdministrativeDomain.cache.percent
Session.cache.percent
RoleAccess.cache.percent
Preference.cache.percent
PagingSession.cache.percent
IBADefinition.cache.percent
EnumerationDefinitionCache.cache.percent
LWCStructEnumAttTemplate.cache.percent
LWCTypeDefinition.cache.percent
FvVault.cache.percent
IndexPolicyList.cache.percent
The second cache sizing algorithm sizes caches based on the number of users defined in the system and the percentage of those users that are expected to be concurrently executing Windchill requests during peak workloads. The predicted percentage of all users that will be concurrently active is governed by property peakActiveUsersPercent and the default value is 10.
Regardless of which algorithm is executed, the resulting cache size is the larger of the out-of-the-box size and the calculated cache size. A configurable size limit is applied to each cache in case the sizing algorithm over allocates memory. The maximum size for all of the above caches is governed by properties <CacheName>.cache.size.limit that are defined in Configurator.properties. You can override the calculated values when running the assistant interactively For example, the following lines show the lines that set the session cache property:
[echo] Named users: 100
[input] Estimated peak number of active users: [10]
[echo] Expected peak active users: 10
[echo] Configuring wt.cache.size.SessionCache currentSize=500 rowcount=100 percent=20
[input] Set Session Cache Size (max=2000): [500]
After sizing the data caches, the assistant then considers various properties that configure database connections, JDBC statement cache sizes, and so on. These properties all reside in <Windchill>/utilities/wca/Windchill/db/db.properties. Many of these properties have initial sizes that are suited for environments with minimal resources such as laptop or small desktop systems. When configuring Windchill on servers with larger heaps these properties should be adjusted accordingly.