Secondary Storage


Q1.

Consider a typical disk that rotates at 15000 rotations per minute (RPM) and has a transfer rate of 50x10^{6} bytes/sec. If the average seek time of the disk is twice the average rotational delay and the controller's transfer time is 10 times the disk transfer time, the average time (in milliseconds) to read or write a 512-byte sector of the disk is ______.
GateOverflow

Q2.

Six files F1, F2, F3, F4, F5 and F6 have 100, 200, 50, 80, 120, 150 records respectively. In what order should they be stored so as to optimize act. Assume each file is accessed with the same frequency
GateOverflow

Q3.

For a magnetic disk with concentric circular tracks, the seek latency is not linearly proportional to the seek distance due to
GateOverflow

Q4.

Consider a disk pack with a seek time of 4 milliseconds and rotational speed of 10000 rotations per minute (RPM). It has 600 sectors per track and each sector can store 512 bytes of data. Consider a file stored in the disk. The file contains 2000 sectors. Assume that every sector access necessitates a seek, and the average rotational latency for accessing each sector is half of the time for one complete rotation. The total time (in milliseconds) needed to read the entire file is ____________.
GateOverflow

Q5.

Consider a disk pack with 16 surfaces, 128 tracks per surface and 256 sectors per track. 512 bytes of data are stored in a bit serial manner in a sector. The capacity of the disk pack and the number of bits required to specify a particular sector in the disk are respectively:
GateOverflow

Q6.

In case of a DVD, the speed of data transfer is mentioned in multiples of?
GateOverflow

Q7.

A disk has 8 equidistant tracks. The diameters of the innermost and outermost tracks are 1 cm and 8 cm respectively. The innermost track has a storage capacity of 10 MB. If the disk has 20 sectors per track and is currently at the end of the 5^{th} sector of the inner-most track and the head can move at a speed of 10 meters/sec and it is rotating at constant angular velocity of 6000 RPM, how much time will it take to read 1 MB contiguous data starting from the sector 4 of the outer-most track?
GateOverflow

Q8.

Formatting for a floppy disk refers to
GateOverflow

Q9.

Which of the following RAID level provides the highest Data Transfer Rate (Read/Write)
GateOverflow

Q10.

A magnetic disk has 100 cylinders, each with 10 tracks of 10 sectors. If each sector contains 128 bytes, what is the maximum capacity of the disk in kilobytes?
GateOverflow