Why does shortest seek time first policy suffer from starvation?

Shortest Seek Time First ( SSTF ) SSTF suffers from starvation. SSTF satisfies the request which is at the shortest distance from the read-write head. Due to this, the read-write head will never be able to read track 100 since all the new upcoming read requests will be at a shorter distance from the read-write head.

What is the difference between FCFS and SSTF?

Calculate the total number of track movements of Read/Write head using SSTF algorithm….Difference between FCFS and SSTF disk scheduling algorithm :

	FCFS SCHEDULING ALGORITHM	SSTF SCHEDULING ALGORITHM
1.	FCFS is not efficient in seek movements.	SSTF is very effective/efficient in seek movements.

What are the advantages of shortest seek time first and Scan Disk scheduling algorithm?

Advantages of Shortest Seek Time First (SSTF) –

Better performance than FCFS scheduling algorithm.
It provides better throughput.
This algorithm is used in Batch Processing system where throughput is more important.
It has less average response and waiting time.

How do you calculate total seek time?

A hard disk system has the following parameters : Number of tracks = 500 Number of sectors/track = 100 Number of bytes /sector = 500 Time taken by the head to move from one track to adjacent track = 1 ms Rotation speed = 600 rpm.

Is starvation possible in scan?

Starvation is avoided in SCAN algorithm. Low variance Occurs in waiting time and response time.

Is SSTF optimal?

Although, SSTF is not optimal, it is faster than the other 3 because it services the closest request first.

Which is better SSTF or scan?

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 are the different disk scheduling algorithms?

Disk Scheduling Algorithms

FCFS scheduling algorithm.
SSTF (shortest seek time first) algorithm.
SCAN scheduling.
C-SCAN scheduling.
LOOK Scheduling.
C-LOOK scheduling.

What does seek time mean in computer terms?

Definition of seek time : the length of time it takes for a disk drive to locate a given piece of information on a disk.

Which 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.

How do you find the shortest seek time?

Shortest seek time first (SSTF) algorithm selects the disk I/O request which requires the least disk arm movement from its current position regardless of the direction. It reduces the total seek time as compared to FCFS.

What C looks like in OS?

C-LOOK is the modified version of both LOOK and SCAN algorithms. In this algorithm, the head starts from first request in one direction and moves towards the last request at other end, serving all request in between.