CPU load constraint.
As #4038, but for Tasks and ECUs.
#2 Updated by Simon Barner 4 months ago
Underlying load annotation to be implemented in #4047.Semantics for constraint formalization:
- load = Maximum percentage that the sum of the WCETs of all tasks allocated to an ECU may consume of the LCM of these tasks' periods.
- Tasks t1, t2, t3 with WCET 0.002s, 0.007s and 0.1s.
- Period of tasks 0.2s, 0.1s, 0.4s -> LCM = 0.4s
- Expressed as periodic constraint of the respective task
- Shortcut: in case the period is not specified of a certain task, it is assumed to be identical as for the other tasks. Therefore, if different periods are provided for at least two tasks, then the period has to be explicitly specified for all tasks. Otherwise, if all periods are the same, then it is enough to specify it for one tasks, only.
- Sum of WCETs = 0.002s + 0.002s + 0.007s + 0.007s + 0.007s + 0.007s + 0.1s = 0,132s
- Effective load = 0,132s/0,4s = 0,33