Ace test series

Question

Which of the following scheduling algorithms can cause indefinite blocking of a process?

a>FIFO

b>SRTF

c>Round Robin

d>Priority scheduling

 

According to me answer should be B and D.Am I correct??

Answer 1

Indefinite blocking is the another term for starvation .. Meaning that a process may never be allowed to execute in the running state..This happens in SRTF and priority scheduling ..

This can be explained as :

As soon as the process having shortest remaining time is there , then another process of shorter time burst may arrive , or equivalently of higher priority may arrive in the ready queue..Hence starvation is possible in case of both of these..

As opposed this , the order in FCFS is defined already by the order in which they arrive in ready queue and hence ready state ..Same is the case of round robin algorithm..

Hence both B) and D) are correct answers..

Comments

Thank you and can you take a look at this question

https://gateoverflow.in/94287/made-easy-test-series#c94612

Answer 2

Yes, because a new process can come with higher priority or shortest job and starve a job with lower priority job.

Answer 3

Yes, in SRTF if a shorter job keep on coming so longer job have to wait for indefinte time, same for priority as well .

Answer 4

Any priority based algorithm can lead to starvation. (Source of statement: Operating System Concepts, Galvin)

FIFO: No priority. Serve processes in order they arrive. Every process has equal priority. No starvation possible.

SJF/SRTF: Priority Based. Priorities are assigned based on remaining time. The process with lesser remaining time wins the contention. Can lead to starvation.

Round Robin: No priority. CPU scheduer treats ready queue as a circular queue and goes around giving equal slots of time to each process. No starvation is possible.

Priority Based: The name itself says priority. Can lead to starvation.

So yeah, options B and D are both correct.