Unit 2: Processes and Process scheduling

Question 1

What is a process?

Answer 1

An executing program.

Question 2

What are the three process states?

Answer 2

Running, Ready, and Blocked.

Question 3

In processing, “running” is when………..

Answer 3

the CPU is actually being used.

Question 4

In processing, “ready” is……….

Answer 4

runable, but has no CPU access.

Question 5

In processing, “ blocked” is………..

Answer 5

waiting for an external event to occur.

Question 6

What are the two process conditions?

Answer 6

Processor Bound and I/O Bound.

Question 7

What is preemptive scheduling?

Answer 7

processes give up CPU based on clock interrupt.

Question 8

What is Non-preemptive scheduling?

Answer 8

Processes voluntarily give up the CPU (run til done).

Question 9

In scheduling, the amount of useful work accomplished per unit time is called ………..

Answer 9

Throughput

Question 10

In scheduling, the fraction of time the device is busy is called …………

Answer 10

Utilization

Question 11

What is Turnaround time?

Answer 11

The length of time between when the job arrives in the system and when it finally finishes.
•(exit time - arrival time)

Question 12

What is wait time?

Answer 12

The amount of time the job is ready.
• ( turnaround time - execution time )

Question 13

What is response time?

Answer 13

The length of time between when the job arrives in the system and when it starts to produce output.
• ( first execution time - arrival time )

Question 14

What are the three levels of scheduling

Answer 14

Admission, Memory, and CPU.

Question 15

Is FIFO preemptive or non-preemptive?

Answer 15

Non-preemptive

Question 16

Is the shortest first algorithm preemptive or non-preemptive?

Answer 16

Non-preemptive

Question 17

Is the shortest remaining algorithm preemptive or non-preemptive?

Answer 17

Preemptive

Question 18

A scheduler that runs the first on the queue until it blocks, then runs the next, and so on is called ……….

Answer 18

FCFS

Question 19

Whenever the CPU chooses the process with the shortest execution time to run first, it is called ……….

Answer 19

SJF

Question 20

The scheduler that runs the process with the shortest remaining time first is called …………

Answer 20

SRTN

Question 21

The preemptive version of the SJF is known as ………

Answer 21

SRTN

Question 22

The scheduler that is like FCFS, but after a length of time, quantum, if the current process is not completed it is moved to the end of the queue after the next process has started is called …

Answer 22

Round Robin

Question 23

The scheduler that always runs the process with the highest priority first, and can be either preemptive or non-preemptive, is called ….

Answer 23

Priority Scheduling

Question 24

A process being allowed to run even though it has the lowest priority is called …

Answer 24

Priority Inversion