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Feature #4040

CPU load constraint.

Added by Simon Barner 3 months ago. Updated about 1 month ago.

Status:
New
Priority:
Low
Assignee:
Category:
-
Start date:
07/01/2020
Due date:
% Done:

0%

Estimated time:

Description

As #4038, but for Tasks and ECUs.


Related issues

Related to Feature #4047: Reconfiguration synthesis related parameters for platform architectureIn Progress08/17/202008/21/2020

History

#1 Updated by Simon Barner about 2 months ago

  • Related to Feature #4047: Reconfiguration synthesis related parameters for platform architecture added

#2 Updated by Simon Barner about 2 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.
  • Example
    • 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

#3 Updated by Johannes Eder about 1 month ago

  • Assignee changed from Johannes Eder to Simon Barner

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