Question D $(10$ points$)$: Combined Scheduling

$[1]$ Consider combined scheduling of periodic and aperiodic tasks. Assume the system has two periodic tasks T$1$ and T$2.$ Ti: $($ci$,$ pi$)$; T$1$: $(1,4)$; T$2$: $\backslash ((3,8)\backslash ).$ For scheduling aperiodic tasks, a Server task Ts: $\backslash ((3,12)\backslash )$ is created. Assume that aperiodic tasks $($A$1,$ A$2,$ A$3,$ A$4)$ arrive at times $6,8,11,$ and $15$ and their respective computation times are $\backslash (2,3,3\backslash ),$ and $3$ ; respective absolute deadlines are $\backslash (10,12\mathrm{.}16\backslash ),$ and $20.$

Construct RMS schedule up to time $24$ using the Deferrable Server.

Clearly state which aperiodic tasks met their deadline and which missed their deadline.

Question E $(10$ points$)$: Conceptual question

$[1]$ RMS assigns priority to task based on their periods. However, a task with higher period may be more "important", i$.$e$.,$ it offers higher value to the application, than a task with a lower period. The Application priority of a task needs to reflect its scheduling priority.

Use a simple technique that ensures a task that offers higher value gets higher priority $($as per RMS priority assignment$)$ over tasks that offer lower value.

Apply the technique to the following task set.

$\backslash ($ T i $\backslash )$ : $\backslash (($c i$,$ p i$)$: T $1$:$(2,4),$ T $2$:$(4,8)\backslash ),$ where task $\backslash ($ T $2\backslash )$ is more "important" than task $\backslash ($ T $1\backslash ).$

For this task set, the RMS priority is $\backslash (\backslash$mathrm$\{$T$\}1>\backslash$mathrm$\{$T$\}2\backslash ),$ but the Application priority is $\backslash (\backslash$mathrm$\{$T$\}2>\backslash$mathrm$\{$T$\}1\backslash ).$

Hint: Adjust task parameters preserving its CPU utilization demand.

Note: Adding a "value" parameter $(\backslash ($ v i $\backslash ))$ or the relative deadline $($di$)$ to a task is not a valid answer.

Questions to answer:

$($a$)$ Provide the modified task set?

$($b$)$ Show the RMS schedule using RMS priority for the original task set.

$($c$)$ Show the RMS schedule using Application priority for the modified task set.