released: 02/10, 18:00
due: 02/16, 23:59

Answer the following questions.
Submit your answers to Canvas assignments. There is an entry for this homework.


1. Shortest Time to Completion First

Below is the scheduling game we played in class (with the same assumptions).
Schedule the following processes using STCF scheduling algorithm (2 points)

    Process  Arrival  Running Time
    P1       0        4
    P2       3        3
    P3       4        2
    P4       7        1

1.a Schedule:
    0  1  2  3  4  5  6  7  8  9 



1.b What is the average turnaround time? (1 point)



1.c What is the average response time? (1 point)



2. Round Robin

Below is the scheduling game we played in class (with the same assumptions).
Schedule the following processes using RR scheduling algorithm
with **time slice = 2**. (2 points)

    Process Arrival     Running time
    P1      0           3
    P2      0+\epsilon  2
    P3      0+2\epsilon 5

2.a schedule:

  0  1  2  3  4  5  6  7  8  9




2.b What is the average turnaround time? (1 point)


2.c  What is the average response time? (1 point)




3. Multi-level Feedback Queue

Schedule the processes below [update 2/10: was "blow"; typo] using MLFQ.
HW3 MLFQ works as follows:
  - There are three queues---q1, q2, and q3.
  - The Queues q1,q2 and q3 have priorities high, medium, and low, respectively
  - Among queues, we run Prio algorithm.
    (namely, a process in a lower priority queue runs only when higher priority
    queues are empty.)
  - q1 and q2 run RR with time slice 1 and 2 respectively.
  - q3 runs FIFO.
  - When a process arrives, it is added at the head of q1.
    (namely, the new arrival process will run first.)
  - If a process runs for 4 units in one queue, its priority is reduced
    by one level and the process is moved to the lower queue.


    Process  Arrival  Running time
    P1       0        6
    P2       2        3
    P3       5        4

Schedule:
  0  1  2  3  4  5  6  7  8  9  10  11  12