Domain Objects Default Settings Reference

The Domain Object Default settings apply to all objects except those for which you explicitly configure overrides, using the Domain Object Overrides section. The options are available based on the object management type selected.

For Cache Object Management

Domain Object Default Settings for Cache OM
Property Description
Mode With Cache OM, you can keep memory objects in the cache or Rete network using the following cache modes.
Memory Only
Objects are not persisted in the cache. They are kept in the Rete network (working memory) only.
Cache Only
Objects are persisted in the cache. They must be loaded into working memory as needed. This is the most common choice for a cache cluster.

See Cache Modes and Project Design in TIBCO BusinessEvents Architect’s Guide to understand the effect of this setting.

Default is Cache Only.

Note: Note If you set the mode to Memory Only, the rest of the properties in this section are not relevant and are ignored.
Preload Entities Specifies whether objects are loaded into the cache from the backing store on system startup (both normal startup and recovery).
Checked
All objects are preloaded into the cache from the backing store. Lower level settings can override this setting by excluding specified objects.
Unchecked
No objects are preloaded. into the cache from the backing store. Lower level settings can override this setting by including specified objects.

Default is unchecked.

Preload Handles Specifies whether object handles are loaded into the ObjectTable cache. The ObjectTable cache holds references (handles) to the objects themselves.
Checked
All object handles are preloaded. Lower level settings can override this setting by excluding handles for specified objects.
Unchecked
No object handles are preloaded into the cache from the backing store. Lower level settings can override this setting by including handles for specified objects.

Default is unchecked.

Preload Fetch Size If Preload Entities or Preload Handles or both are checked, this setting specifies the number of entity objects or handles (or both) to preload for each entity type whose objects or handles (or both) are configured to be preloaded.

This setting applies to both objects and handles and cannot be set differently for each.

Objects and handles are fetched in a non-deterministic manner.

This setting can be overridden at the entity level.

Set to 0 to preload all. Set to a number to load that number of objects or handles (or both).

Default is 0.

Note: This setting is ignored unless Preload Entities or Preload Handles or both are checked.
Check for Version This field applies to concepts that use cache-only mode.

An inference agent uses its L1 cache, a local cache of limited size, to improve access time to the concepts stored in the cluster cache. When an agent finds a concept instance in this local cache, the Check for Version setting determines whether the agent will use the instance directly, or instead check in the cluster cache for more recent version.

If Checked
(default value) The agent checks in the cluster cache for a more recent version. If a more recent version exists, it will be used, and will replace the one found in the local cache.
If Not Checked
The agent uses the instance found locally.

When content-aware load balancing is used, the local instance can be used without checking for version, improving performance.

Default is checked.

Evict from Cache on Update

Used only if the Agent.AgentClassName.cacheTxn.updateCache property is set to false (see

CDD Agent Classes Tab Properties Reference).

If selected then whenever a rule action changes the value of any of an entity’s properties or inserts a new entity, the entity instance is evicted from the cache (updates are saved in the backing store).

Use as needed to improve performance and cache memory management. For example, if an entity is not accessed frequently, it may save memory in the cache if the entity is evicted from cache after it is updated.

Is Cache Limited If selected, the cache size is limited.

Limited cache requires use of a backing store. See Configuring a Limited (or Unlimited) Cache.

The size of the entity cache and the size of the object table cache are set in the Object Management section of the Cluster tab.

If not checked, the cache size is unlimited.

You can override this default setting in entity overrides.

Default is unchecked.

Concept TTL Time-to-live (in seconds) for the concept. After the time-to-live is expired, the concept expires within acceptable limits of the timeout.

The default value is -1, which means concept does not expire, and must be explicitly consumed. If you do not need to write the concept to cache, set this field to 0.

Following are some constraints for using the Concept TTL field:

  • Containment relationship: Ensure that parent and child concepts expire together or that the time-to-live for the parent is less than time-to-live for the child concept. Thus, the application never references the child once the parent has expired.
  • Reference Relationships: Do not set this field for concepts that reference other concepts, or for concepts that are referenced in other concepts.

Note: After the time-to-live expires, the concept is removed from the object table after a specified delay interval. This delay helps reduce object table load. You can configure this interval using the objectTable.eviction.delay.interval CDD property. Thus,

Actual eviction time from object table = TTL + objectTable.eviction.delay.interval

The default value is 60 seconds.

For Store Object Management

Domain Object Default Settings for Store OM
Property Description
Mode With Store OM, you can keep memory objects in the store or Rete network using the following modes.
Memory Only
Objects are not persisted in the store. They are kept in the Rete network (working memory) only.
Store Only
Objects are persisted in the store. They must be loaded into working memory as needed. This is the most common choice for a store OM type cluster.

See Cache Modes and Project Design in TIBCO BusinessEvents Architect’s Guide to understand the effect of this setting.

Default is Store Only.

Note: Note If you set the mode to Memory Only, the rest of the properties in this section are not relevant and are ignored.
Concept TTL Time-to-live (in seconds) for the concept. After the time-to-live is expired, the concept expires within acceptable limits of the timeout.

The default value is -1, which means concept does not expire, and must be explicitly consumed. If you do not need to write the concept to store, set this field to 0.

Following are some constraints for using the Concept TTL field:

  • Containment relationship: Ensure that parent and child concepts expire together or that the time-to-live for the parent is less than time-to-live for the child concept. Thus, the application never references the child once the parent has expired.
  • Reference Relationships: Do not set this field for concepts that reference other concepts, or for concepts that are referenced in other concepts.

Note: After the time-to-live expires, the concept is removed from the object table after a specified delay interval. This delay helps reduce object table load. You can configure this interval using the objectTable.eviction.delay.interval CDD property. Thus,

Actual eviction time from object table = TTL + objectTable.eviction.delay.interval

The default value is 60 seconds.