Pattern 37 (Commencement on Allocation)
The ability to commence execution on a work item as soon as it is allocated to a resource.
Work on the Practice Tower Block Fire Drill work item commences as soon as it is allocated to a Fire Team resource.
Although combined creation, allocation and commencement of work items promotes more efficient process throughput, it effectively requires "hardcoding" of resource identities in order to manage work item allocation at creation time. This obviates much of the advantage of the flexible resource assignment strategies offered by PAIS. Commencing work items at the point of allocation does not require resource identity to be predetermined and offers a means of expediting throughput without necessitating changes to the underlying process model.
Where a task is specified as being subject to Commencement on Allocation, the act of allocating an associated work item in a process instance also results in it being commenced. In effect, it is put into the work list of the resource to which it is allocated with a started status rather than an allocated status. This pattern is illustrated by the transition S:start_on_create in Figure 7.
There is no specific context conditions associated with this pattern.
The potential exists to implement this pattern in one of two ways: (1) Commencement on Allocation can be specified within the process model and (2) individual resources can indicate that items in their work list are to be initiated as soon as they are received. WebSphere MQ provides support for the second approach.
An offering achieves full support if it satisfies the description for the pattern.
To achieve a + rating (direct support) or a +/- rating (partial support) the product should satisfy the corresponding evaluation criterion of the pattern. Otherwise a - rating (no support) is assigned.
|Websphere MQ Workflow||3.4||+||Resources can configure work queues to initiate work items on arrival|
|Oracle BPEL||10.1.2||-||Oracle BPEL PM offers no support for this pattern since a resource needs to "accept" or "acquire" a work item from the worklist in order to start the execution|
|jBPM||3.1.4||-||jBPM does not support this pattern, as a work item can not be started by the system. A resource alone can initiate the execution of a work item.|
|OpenWFE||1.7.3||-||OpenWFE does not support this pattern as a work item can not be started by the system. A resource alone can initiate the execution of a work item.|
|Enhydra Shark||2||-||Enhydra Shark does not support this pattern. When a work item is accepted (i.e. allocated, which is done through ticking it in a work list), it is automatically started which is shown by setting its start time. However, the selection (and hence the start) is done by a resource and not by the system.|
Summary of Evaluation