1.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.
- Generalize the result of Problem 11.1 to the case in which a program refers to n
devices. 3. 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 that the diskhead is initially positioned over track 100 and is moving in the direction of decreasing track number.
b. Do the same analysis, but now assume that the disk head is moving in the direction of increasing track number.