Questions from Operating Systems

Q: Consider a program that accesses a single I/O device and

Consider a program that accesses a single I/O device and compare unbuffered I/O to the use of a buffer. Show that the use of the buffer can reduce the running time by at most a factor of two.

Q: A 32-bit computer has two selector channels and one multiplexor

A 32-bit computer has two selector channels and one multiplexor channel. Each selector channel supports two magnetic disk and two magnetic tape units. The multiplexor channel has two line printers, tw...

Q: It should be clear that disk striping can improve the data transfer

It should be clear that disk striping can improve the data transfer rate when the strip size is small compared to the I/O request size. It should also be clear that RAID 0 provides improved performanc...

Q: Consider a 4-drive, 200 GB-per-drive

Consider a 4-drive, 200 GB-per-drive RAID array. What is the available data storage capacity for each of the RAID levels, 0, 1, 3, 4, 5, and 6?

Q: An interactive system using round-robin scheduling and swapping tries to

An interactive system using round-robin scheduling and swapping tries to give guaranteed response to trivial requests as follows. After completing a round-robin cycle among all ready processes, the sy...

Q: Generalize the result of Problem 11.1 to the case in

Generalize the result of Problem 11.1 to the case in which a program refers to n devices. Result of Problem 11.1: If the calculation time exactly equals the I/O time (which is the most favorable situ...

Q: In general terms, what are the four distinct actions that a

In general terms, what are the four distinct actions that a machine instruction can specify?

Q: a. Perform the same type of analysis as that of Table

a. Perform the same type of analysis as that of Table 11.2 for the following sequence of disk track requests: 27, 129, 110, 186, 147, 41, 10, 64, 120. Assume the disk head is initially positioned over...

Q: Consider a disk with N tracks numbered from 0 to (N

Consider a disk with N tracks numbered from 0 to (N-1) and assume requested sectors are distributed randomly and evenly over the disk. We want to calculate the average number of tracks traversed by a...

Q: The following equation was suggested both for cache memory and disk cache

The following equation was suggested both for cache memory and disk cache memory: TS=TC+M×TD Generalize this equation to a memory hierarchy with N levels instead of just 2