A certain moving arm disk storage, with one head, has the following specifications: - Number of tracks per recording surface: (not given, single surface implied) - Disk rotation speed: 2900 rpm - Track storage capacity: 62500 bits The average latency of this device is P ms and the data transfer rate is Q bits/sec. Write the values of P and Q.

GATE 1993 · Operating System · Disk · medium

Answer: P = 10.34 ms (average latency); Q = 3,020,833 bits/sec (approx 3.02 Mbits/s).

1. Compute Period of One Revolution: T_rev = 60 / 2900 s = 0.02069 s = 20.69 ms
2. Compute Average Latency P: P = 20.69 / 2 = 10.34 ms
3. Compute Data Transfer Rate Q: Q = 62500 x (2900 / 60) = 62500 x 48.333... = 3,020,833 bits/sec