Re: Constrained deadlines in SMP
On 31/07/18 15:34, Rúben Gonçalves (1150785) wrote: We are currently running some experiments with RTEMS in SMP and were faced with some problems. We were hoping someone with a better understanding of the operating system mechanisms could help us figure out what to do. We are using the EDF (Earliest Deadline First) scheduler for RTEMS-SMP and the Rate Monotonic Manager. We were trying to run some periodic tasks that have a constrained deadline. (e.g., Task1 - Deadline: 30 ticks - Period: 1000 ticks) The use case of constrained deadlines is currently not supported. I think we would have to modify the rate monotonic objects to support it or create a new object. You have to combine a normal timer for the period with a deadline initialization at period begin. -- Sebastian Huber, embedded brains GmbH Address : Dornierstr. 4, D-82178 Puchheim, Germany Phone : +49 89 189 47 41-16 Fax : +49 89 189 47 41-09 E-Mail : sebastian.hu...@embedded-brains.de PGP : Public key available on request. Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG. ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
Constrained deadlines in SMP
We are currently running some experiments with RTEMS in SMP and were faced with some problems. We were hoping someone with a better understanding of the operating system mechanisms could help us figure out what to do. We are using the EDF (Earliest Deadline First) scheduler for RTEMS-SMP and the Rate Monotonic Manager. We were trying to run some periodic tasks that have a constrained deadline. (e.g., Task1 - Deadline: 30 ticks - Period: 1000 ticks) The problem is that our deadline does not correspond to the period of the task and so, we've come to the conclusion that we needed to create 2 rate monotonic periods (one with the period and other with the deadline) in order to define the actual deadline of our task, but that would involve creating a third period to validate in the end the meeting of our actual deadline (because of details in the implementation). We would like to know if we are missing any vital information regarding the RTEMS in SMP that would make our development of this solution more practical and also, how is the dynamic priority of a task represented in the system using EDF and RMM? Thanks in advance, Ruben e Joel. ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
