timing_exam 5)

examples/timing_exam.rs

@@ -401,5 +401,25 @@ const APP: () = {
 // - How would an ideal tool for static analysis of RTIC models look like.
 //
 // [Your ideas and reflections here]
+// RTIC has very little overhead compared to other solutions that use a thread based approach. In
+// real time system it is very important that the overhead is small and that the system behavior is
+// easy to predict. RTIC is very good at both, but the thread based approach is much worse in both
+// aspects. It is much harder to follow the task execution order in a thread based system because
+// it has less restrictions. It is also because it has less restrictions that the overhead is
+// larger.
+//
+// From this exam it is clear that the theoretical model is very close to the measured results,
+// but there are some small differences caused by the inaccuracy of machines that can make a big
+// difference. These inaccuracies are extremely hard to account for because there are so many factors
+// that can change the result. And as we can see from this exam a difference of just a couple of
+// cycles can cause the result to be way different.
+//
+// I think the ideal tool would have to take the overhead into account in some way. The exact
+// overhead is hard to know, thus i think the tool should give 2 sets of analysis. One that is the
+// pure theoretical analysis and this could be seen as the lower bound. Then a second one that
+// takes assumes that the overhead is large enough to cause the analysis to be different and this
+// can be seen as the worst case. From this we could also get the needed overhead for the second
+// analysis to happen. This gives a good understanding of the behavior of the system and how much
+// overhead it tolerates before it becomes worse then it theoretically should be.
 //
 // Commit your thoughts, we will discuss further when we meet.