In: Computer Science
uppose the following scenarios to discuss the impact effecting on the degree of multiprogrammingand context switching time?
Scenario1:all the processes in the ready queue are classified as I/O bound –process.
Scenario 2:All the processes in the ready queue are classified as CPU bound –process.
Scenario 3:Most of the processes in the ready queue are classified asmix of I/O bound –processes and CPU-bound processes
Greetings!!
Scenario 1:
When all the processes in the ready queue are I/O bound, all will be completing their short CPU burst and enter into the I/O queue. This makes the CPU to be idle and hence the scheduler increases the number of jobs ie degree of multiprogramming is increased. Since the number of processes are high and all of these are switching frequently, the context time also is very high.
Scenario 2:
When all the processes are CPU bound, once a job is submitted it will continue executing for long time. This makes the CPU busy and hence no more new processes will be added and hence the degree of multiprogramming will be low. Since there are less number of CPU bounded processes and the frequency of switching will be very less and hence the context switch time also is less.
Scenario 3:
Since the ready queue has a good mix of processes the scheduler will not add more processes and hence the degree of multiprogramming remains average and the context switch time also remains average.
Hope this helps