The Methods & Tools Special Interest Group met from 4 pm till 5:30 pm Central European Time.
Agenda:
- Threading models applied to CAPE-OPEN applications
Participants
AmsterCHEM (represented by Jasper van BATEN), Bryan Research & Engineering (represented by Michael HLAVINKA), Michel PONS (contractor to CO-LaN as Chief Technology Officer). Apologies received from U.S. Environmental Protection Agency (represented by Bill BARRETT).
Methods & Tools Special Interest Group progressed further chapter 5 of the document describing COBIA Threading Models. This meeting delivered version 27 of the document.
Chapter 5 comes after a chapter that summarizes the COM Threading Models since a comparison is made in chapter 5 between the COBIA and the COM Threading Models, and also, later, an explanation how the Threading Models for both middleware “work” together.
Section 5.1 covers the requirement that the COBIA Threading Models must fulfilled, mainly that the PME must not concurrently access a primary PMC object, or any of its secondary objects, even for PMCs that advertise as multi-threading capable.
Section 5.2 defines the two Threading Models in COBIA, namely the DEFAULT and the RESTRICTED models. While not changing the design, the text defining both models has been reworked, with the intent of clarifying the definitions. The DEFAULT model is that a PME can invoke methods in PMCs from any thread, while being subject to the requirement above. The RESTRICTED model is that the PME may invoke a PMC only on a single thread, the one in which the PMC was created.
Section 5.2.1 (may be still subject to further number change) covers some “implementation” details of the COBIA Threading Models, namely the registration and instantiation flags used to specify the COBIA Threading Models advertised and/or chosen.
A PMC advertises its threading capabilities through its registration in the COBIA registry: a PMC is either capable of DEFAULT threading or the PMC requires RESTRICTED threading.
A PME indicates, at creation time of a PMC, whether access made by the PME to the PMC complies with the restrictions implied by the RESTRICTED model or not. The specific case where a PMC is created through a Manager is explained there as well.
All the comments made previously in reviews of these sections have been dealt with.
M&T SIG needs still to address mainly chapter 6 that describes points related to COM-COBIA interoperability.
