Fcfs scheduling algorithm, Operating System

Assignment Help:

Q. Presume that the following processes arrive for execution at the times indicated. Every process will run the listed amount of time. In responding the questions use non pre-emptive scheduling and base all decisions on the information you have at the time the decision must be made.

780_FCFS scheduling algorithm.png

a. What is the average revolve time for these processes with the FCFS scheduling algorithm?

b. What is the average revolve time for these processes with the SJF scheduling algorithm?

c. The SJF algorithm is supposed to improve performance however notice that we chose to run process P1 at time 0 because we did not know that two shorter processes would arrive soon. Calculate what the average turnaround time will be if the CPU is left idle for the first unit and then SJF scheduling is used. Keep in mind that processes P1 and P2 are waiting during this idle time thus their waiting time may increase. This algorithm could be recognized as future-knowledge scheduling.

Answer:

a. 10.53

b. 9.53

c. 6.86

Keep in mind that turnaround time is finishing time minus arrival time so you have to subtract the arrival times to compute the turnaround times. FCFS is 11 if you overlook to subtract arrival time.


Related Discussions:- Fcfs scheduling algorithm

What advantages are there to this two-level directory, What advantages are ...

What advantages are there to this two-level directory? Users are isolated from each other. Users have more freedom in choosing file names.

Program, i need the job to be done within 3days

i need the job to be done within 3days

Describe paging algorithm needs a reference bit, Q. Suppose that you want ...

Q. Suppose that you want to utilize a paging algorithm that requires a reference bit (such as second-chance replacement or working-set model) however the hardware does not provide

Different ways in which a thread can be cancelled, What are the different w...

What are the different ways in which a thread can be cancelled? Cancellation of a target thread may happen in two different scenarios: Asynchronous cancellation: One thr

What is the use of system programs, Q. What is the use of system programs? ...

Q. What is the use of system programs? Answer: System programs are able to be thought of as bundles of useful system calls. They provide fundamental functionality to users so

Rule a magnetic hard disk, Q. If magnetic hard disks eventually have the s...

Q. If magnetic hard disks eventually have the same cost per gigabyte as do tapes will tapes turn into obsolete or will they still be needed? Describe your answer. Answer: Tap

Cache replacement policies, The physical memory acts as a cache backed by t...

The physical memory acts as a cache backed by the disk. When the physical memory is full, and we want to read in another page from disk, we have to evict a page from physical memor

Explain benefits of time-sharing system, Under what circumstances would a ...

Under what circumstances would a user be better off using a time-sharing system, rather than a personal computer or single-user workstation? When there are some other users, th

Could you replicate a multilevel directory structure, Q. Could you replica...

Q. Could you replicate a multilevel directory structure with a single-level directory structure in which arbitrarily long names can be used? If your answer is yes describe how you

Difference between preemptive and nonpreemptive scheduling, Define the diff...

Define the difference between preemptive and nonpreemptive scheduling. State why strict nonpreemptive scheduling is unlikely to be used in a computer center. Preemptive schedul

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd