About Station Affinities

You can define affinities to control which workitems are dispatched to a particular SIMULIA Execution Engine station. If a station is to have specific affinity keywords associated with it, you must include the keywords in the station.properties file.

Affinities are properties that SIMULIA Execution Engine stations may be declared to have. Individual components in a model may be set to have one or more affinities, so that workitems for running these components may be dispatched only to stations declared to have matching affinities. For example, an Excel component is preset to have the Windows affinity because Excel runs only on Windows; hence, the component will be executed only on a station running on a Windows computer.

Predefined affinities include the station name, OS type, OS name, OS version, and OS architecture. In addition to the predefined affinities, you can set custom and required affinities.

Custom Affinities

A SIMULIA Execution Engine administrator can define custom affinities to control workitem dispatches in the local SIMULIA Execution Engine environment. For example, if NASTRAN runs on only one computer, a station running on that computer could be declared to have the affinity “Nastran” so that all workitems for NASTRAN jobs would automatically be dispatched there. By default, a station has no custom affinities.

Required Affinities

A SIMULIA Execution Engine administrator can define required affinities for stations. For example, you can define a required affinity so that only NASTRAN jobs will be dispatched to the station running on the computer with NASTRAN.

A required affinity becomes a precondition to a workitem to be dispatched to the station. Thus, only components with that affinity will be sent to that station. To define a required affinity in the station.properties file, add a “+” before the affinity. A required affinity is indicated by a +affinity entry in the properties file.

For example, suppose you have a single SIMULIA Execution Engine station with APPL_X installed. If you only define a normal affinity for APPL_X on that station, you can then use that affinity in your SIMULIA Execution Engine model to make sure that the component that runs that application—for example, a Simcode component—will get dispatched to that station. This is normal affinity behavior. However, this does not prevent other, unrelated work from also being dispatched to your APPL_X station; for example, other task, calculator, or Simcode components. These workitems can deplete resources on this station that you may prefer be dedicated to just running APPL_X.

To create a SIMULIA Execution Engine station dedicated solely to APPL_X work, you can specify the station affinity as +APPL_X. This means that not only will components with this affinity be dispatched to this station, but components that do not have that affinity will be excluded from being dispatched to the station.

You can also give a SIMULIA Execution Engine station more than one required affinity. Therefore, a component must have both of the required affinities to run on that station.