Investigate getPeriod accuracy about bart HOT 1 CLOSED

Here is what I do for calculating the period of the task:

Let's say a task started execution at the following times

                       T_1, T_2, ...T_n

Currently for align = "start" the period is

Average of:

                (T_2 - T_1), (T_4 - T_3), ....(T_n - T_{n-1})

In this method we have an edge condition when a task does not run for a particular time or when it migrates between CPUs causing the average to end up significantly higher than the actual period of the task. However, as periodicity is statistical in nature and can vary during the lifetime of the task, we can have a good understanding of the periodicity by getting the median period of the deltas above.

from bart.