Question

Five jobs a, b, c, d and e are waiting in ready queue. Their expected runtimes are 9, 6, 3, 5 and x respectively. All jobs entered in ready queue at time zero. They must run in _____ order to minimize average response time if 3 < x < 5​

Answer 1

Given:

Five job seekers a, b, c, d and e are in a queue.

Expected run times are 9 , 6, 3, 5, and x , where 3 < x < 5.

To Find:

Their  order to minimize average response time .

Solution:

Given that a takes most time of 9 units (minutes).

• So a should be at the end so that a's run time will not affect the rest.

Since b takes 6 units,

• b should be the second from the last.

We can follow the same logic and see that the best order for minimizing the average response time will be :

• c - 3 minutes
• e - x minutes 3< x< 5
• d - 5 minutes
• b - 6 minutes
• a - 9 minutes

They must run in c, e, d, b, a order to minimize average response time.