a$)$ Table $3$ shows the process scheduling for five processes. Each process has its own service time $T_s.$ The turnaround time $($TAT$)$ is the residence time, $T_r,$ or total time spent in the system. Assume that the dispatcher time is negligible $($around $2$ ms $)$ compared to the service time $($in the order of a second$).$

Table $3.$ Processes Scheduling

$\backslash$table$[[$Process ID$,$Arrival Time $($in s$),$Service Time $($in s$)],[$A$,0,4],[$B$,2,10],[$C$,4,3],[$D$,8,8],[$E$,9,5]]$

Show the execution pattern for the following uniprocessor scheduling algorithm:

i$.$ First$-$come$-$first$-$served $($FCFS$).$

$(3$ marks$)$

ii$.$ Round robin $(RR)$ with time quantum, $q=4.$

$(3$ marks$)$

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ECIE $4314$ Operating Systems

iii. Shortest process next $($SPN$).$

$(3$ marks$)$

iv$.$ Shortest remaining time $($SRT$).$

$(3$ marks$)$

v$.$ Highest response ratio next $($HRRN$)($Hints: $R=\frac{s+w}{s},R$ is the response ratio, $w$ is the time spent waiting for the processor, $s$ is the expected service time$).$

$(3$ marks$)$

Suppose that now we have a dual$-$core system:

vi$.$ Formulate the execution pattern for the multiprocessor scheduling algorithm using FCFS and SRT for the processes listed in Table $3.$

$(3$ marks$)$

vii. Evaluate the performance of part $($vi$)$ using Normalized Turnaround Time $(\frac{T_r}{T_s}).$ Select your optimum multiprocessor scheduling algorithm based on its performance and complexity.

$(3$ marks$)$