MCS-284 Chapter 8 Homework (Fall 2002)
When turning in a homework problem, you
should indicate the number I give with an x in it (8.x1).
This will be the reference number I use in reporting back
your standing on the homework.
Problem 8.x1: Suppose we want to design a system to handle 10,000 disk read requests
per second. Each request is for a randomly located 8 KB block on
disk drives with the following specs:
Assume there is no controller overhead or time spent running software
in the processor. Assume also that the workload is spread evenly over
the disk drives. Assume that there are 1000 K in an M. How many
drives and buses are needed? Justify your answers. In calculating the
necessary number of buses, be sure to show that you have considered
both limitations of the buses.
- 12,000 RPM rotational speed
- 7.3 ms average seek time
- 40 MB/s transfer rate.
- interface is via a Ultra/160 bus that can handle 160 MB/s and up
to 31 drives
Instructor: Max Hailperin