Question

Describe the factors that contribute to a disk drive’s average access time. Which of these factors is improved if the spin rate is increased? Which is improved if areal density is increased?

Answer 1

Answer:

1. factors that contribute to a disk drive average access time : position of a read/write head in a track, switch between read/write heads, search for the correct sector to rotate read/write heads
2. Rotational delay
3. track to track seek time

Explanation:

position of a read/write head in a track : the position of a read/write head in a track contributes to a disk drive's average access time because the time required to move from one track to another in order to locate the position of a read/write head is measured in milliseconds.

switch between read/write heads: a set of read/write head is usually shared by a disk drive and this read/write head has to be well attached electronically to ensure the proper location of a sector and this contributes to the average access time of a disk drive.

search for the correct sector to rotate read/write heads : the controller waits for the sector positioned over the head of a read/write head to rotate and the controller continues to monitor and keep records of these rotations until the desired/correct sector is found by the controller. after this the read/write operation is carried out.  

Answer 2

Answer:

See Explanation Below

Explanation:

The question is divided into three parts

1. Describe the factors that contribute to a disk drive’s average access time.

The answer to this is

a. Rotational Delay

b. Track-to-Track seek time or head movement

c. Head to head switching time

Each of the aforementioned factors affects the disk drive's average access time.

The rotational delay is the time between information requests and how long it takes the hard drive to move to the sector where the requested data is located

Track to track is the amount of time it takes the read/write head to search or seek between adjacent tracks

Head to head switching is an action taken by the hard drive head that moves the current action being performed on one read/write head to another

2. Which of these factors is improved if the spin rate is increased?

In the aforementioned factors, the rotational delay gets decreased when the spin rate gets increased.

3. Which is improved if areal density is increased?

The track to track seek time gets improved; the reason for this is that the the increment in the areal density makes the tracks to become narrowed and tightened together.