You can optimize the performance of the workflow user cache by configuring the timeout property and setting the refresh interval.
For performance reasons, workflow user and group information that is returned by the directory service provider is stored in cache memory. With the user and group information in cache memory, the information can be accessed without requiring the workflow system to communicate immediately with the directory service provider. To keep the user and group information current, a background process periodically refreshes the workflow environment records from the directory service provider. Hence, a workflow process does not have to wait for current user information because the information in the workflow environment record is always current.
When the workflow system accesses a user or group record for processing, the workflow user cache is checked for this record. If the record is not cached or the record in memory is stale (that is, no longer valid), the workflow system checks the workflow environment record. In a similar manner, if the record is not in the workflow environment record or the workflow environment record is stale, the workflow system refreshes the record from the directory service provider. Accessing the directory service provider is the most costly process during a record refresh.
Each record, whether cached or in the workflow environment records, has a time stamp of the last update. The time stamp is used to determine whether a record is stale. In this case, a record is considered stale when the time stamp of the last update is older than the number of hours that is specified in the Cached Entry Timeout property value.
You can use Administration Console for Content Platform Engine to configure the Cached Entry Timeout property on the Advanced tab of the workflow system. The Cached Entry Timeout property sets the interval, in hours, for refreshing entries in the workflow user cache.
Configure the Cached Entry Timeout setting based on how often there are changes to your directory service provider, that is, adding or deleting users and groups, or modifying group memberships.
The background process that refreshes the workflow environment records is initiated when Content Platform Engine is started. The background process uses an algorithm that calculates the optimal number of records that are near expiration to refresh, and updates that subset of records at the interval that is specified through the CacheSyncInterval property.
You can use Administration Console for Content Platform Engine to configure the CacheSyncInterval property on the Advanced tab of the workflow system. The refresh interval is set in increments of seconds with a default value of 120 seconds. Set an appropriate refresh value for your business environment.
To manually refresh the workflow user cache, use the vwtool environment command to reconcile user data inconsistencies in the cache.