Contents
What does disk scheduling do?
Disk scheduling is done by operating systems to schedule I/O requests arriving for the disk. Disk scheduling is also known as I/O scheduling. Multiple I/O requests may arrive by different processes and only one I/O request can be served at a time by the disk controller.
What is difference between scan and Cscan?
The only difference between SCAN and CSCAN is that in CSCAN, it begins its scan toward the nearest end and works it way all the way to the end of the system. Once it hits the bottom or top it jumps to the other end and moves in the same direction,unlike the SCAN which moves back to upside using the same path.
What is scan algorithm in operating system?
It is also called as Elevator Algorithm. In this algorithm, the disk arm moves into a particular direction till the end, satisfying all the requests coming in its path,and then it turns backand moves in the reverse direction satisfying requests coming in its path.
What is the best disk scheduling algorithm?
With the classical approach of disk scheduling algorithm, few algorithms like SSTF and LOOK will be the most efficient algorithm compared to FCFS, SCAN, C-SCAN and C-LOOK disk scheduling algorithm with respect to these parameters.
Is there any difference between SSTF and scan scheduling?
C-SCAN algorithm provides low variance in average waiting time and response time. Whereas SSTF provides high variance in average waiting time and response time.
What is difference between scan and FCFS disk scheduling algorithm?
Calculate the total number of track movements of Read/Write head using FCFS….Example:
| Sr.No. | FCFS Disk Scheduling Algorithm | SCAN Disk Scheduling Algorithm |
|---|---|---|
| 3. | FCFS algorithm gives the lowest throughput among all the disk scheduling algorithms. | SCAN algorithm has a better throughput than FCFS scheduling algorithm. |
How does C SCAN disk scheduling algorithm work?
C-SCAN Disk Scheduling Algorithm- Circular-SCAN Algorithm is an improved version of the SCAN Algorithm. Head starts from one end of the disk and move towards the other end servicing all the requests in between. After reaching the other end, head reverses its direction. It then returns to the starting end without servicing any request in between.
Which is an enhanced version of scan disk scheduling?
C-SCAN is an enhanced version of SCAN disk scheduling. In the C-SCAN disk scheduling algorithm, the disk head starts to move at one end of the disk and moves towards the other end and service the requests that come in its path and reach another end. After doing this, the direction of the head is reversed.
Are there any disadvantages to scan disk scheduling?
In SCAN disk scheduling, there is a low variance of response time. In this algorithm, throughput is high. Response time is average. In SCAN disk scheduling, there is no starvation. The disadvantages of SCAN disk scheduling algorithm are:
How is disk scheduling done in an operating system?
Disk scheduling is done by operating systems to schedule I/O requests arriving for the disk. Disk scheduling is also known as I/O scheduling.