Introduction to Computer Systems - Fundamentals of Computer Organization and Architecture - page 12

ways of evaluating the speedup for given partial or general improvement measure-
ments of a machine were discussed at the end of this Chapter.

EXERCISES

1. What has been the trend in computing from the following points of view?
(a) Cost of hardware
(b) Size of memory
(c) Speed of hardware
(d) Number of processing elements
(e) Geographical locations of system components
2. Given the trend in computing in the last 20 years, what are your predictions
for the future of computing?
3. Find the meaning of the following:
(a) Cluster computing
(b) Grid computing
(c) Quantum computing
(d) Nanotechnology
4. Assume that a switching component such as a transistor can switch in zero
time. We propose to construct a disk-shaped computer chip with such a com-
ponent. The only limitation is the time it takes to send electronic signals from
one edge of the chip to the other. Make the simplifying assumption that elec-
tronic signals can travel at 300,000 kilometers per second. What is the limit-
ation on the diameter of a round chip so that any computation result can by
used anywhere on the chip at a clock rate of 1 GHz? What are the diameter
restrictions if the whole chip should operate at 1 THz 10 12 Hz? Is such a

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chip feasible?
5. Compare uniprocessor systems with multiprocessor systems in the following
aspects:
(a) Ease of programming
(b) The need for synchronization
(c) Performance evaluation
(d) Run time system
6. Consider having a program that runs in 50 s on computer A, which has a
500 MHz clock. We would like to run the same program on another machine,
B, in 20 s. If machine B requires 2.5 times as many clock cycles as machine
A for the same program, what clock rate must machine B have in MHz?
7. Suppose that we have two implementations of the same instruction set archi-
tecture. Machine A has a clock cycle time of 50 ns and a CPI of 4.0 for some
program, and machine B has a clock cycle of 65 ns and a CPI of 2.5 for the
same program. Which machine is faster and by how much?