The Methods & Tools Special Interest Group met today from 3 pm till 4:50 pm Central European Time.
Agenda
- Progress on COBIA Phase III development
Participants
U.S. Environmental Protection Agency (represented by Bill BARRETT), AmsterCHEM (represented by Jasper van BATEN), Bryan Research & Engineering (represented by Michael HLAVINKA), Michel PONS (contractor to CO-LaN as Chief Technology Officer).
Highlights
Jasper van BATEN started by demonstrating an add-on to Microsoft Visual Studio to more easily debug COBIA-based applications. Once completed, AmsterCHEM may release it along with the COBIA Wizard, another add-on to Microsoft Visual Studio that complements the command line code generator distributed by CO-LaN in the COBIA Software Development Kit.
Next M&T SIG reviewed what remains to be done in Work Package 1 of COBIA Phase III.
Within the tasks already listed in the scope of Work Package 1, remains to be carried out the task of developing the capability to generate on-the-fly stub code of proxy interfaces that are non-CAPE-OPEN interfaces. Such interfaces can be private between software implementations which are COBIA-based. As COBIA middleware does not know about these interfaces at compilation time, COBIA middleware cannot be distributed with precompiled proxies for such interfaces. A vendor can opt to precompile proxies for vendor-specific interfaces, for the platform at which the vendor’s software runs. Providing the ability to automatically create proxies for interfaces unknown to COBIA at compilation time, eliminates the rather cumbersome task for software vendors to supply proxies.Therefore the ability to create proxies on the fly is an important feature. The mechanism has already been prototyped and will be using the libffi library.
Therefore, M&T SIG will request Management Board to launch a work order for performing the above described development.
The scope given to Work Package 1 was to develop marshalers and to specify how the data used for method invocations are standardized for transport across process boundaries. This requirement was fulfilled using TCP/IP (Transmission Control Protocol/Internet Protocol) as the transport mechanism. TCP/IP is the most generic form of transport and can be used for all marshaling scenarios, including in-process, out-of-process components on a single machine, and to access components on remote machines. This was demonstrated at the CAPE-OPEN 2021 Annual Meeting within the presentation giving the status of COBIA Phase III.
Due to the overhead inherent to the TCP/IP transport protocol and its many layers, relying always on it, leads to sub-optimal marshalling on a single machine. In this configuration, the transport can be rather done using a shared memory space that can be written to and accessed by both the caller and the callee. Creation of such a more optimized transport mechanism will allow more reliable comparison of COBIA marshaling to other marshaling protocols, such as COM-based marshaling.
M&T SIG is therefore proposing to CO-LaN Management Board to launch an additional task within Work Package 1 in order to implement a more appropriate data transport mechanism when marshaling takes place within a single machine.
