CECS 570 -- Assignment 1 (10 points)
Due Wednesday, 2/6/08
1. A multiprocessor consists of 100 processors, each capable of a peak execution rate of 2
Gflops. What is the performance of the system as measured in Gflops when 10% of the code
is sequential and 90% is parallelizable?
2. Suppose a sequential widget-assembly machine can assemble one widget every 3 seconds,
and a 3-way data parallel widget-assembly machine is capable of producing three widgets
every three seconds.
a. How much time does it take to produce 100 widgets using (i) the sequential machine, and
(ii) the parallel machine? What is the speedup?
b. How many widgets must the parallel machine assemble in order to achieve a speedup of
3 over the sequential machine? Justify your answer.
3. Is if possible to have a system efficiency (E) of greater than 100%? Discuss.
4. If today's workstations execute at 108 operations per second, and performance increases at a
rate of 25 percent per year, how long will it be before we have workstations capable of 109
operations per second? 1012?
5. A climate model requires 1016 floating point operations for a ten-year simulation. How long
would this computation take at 1Gflops?
6. A climate model generates 1011 bytes of data in a ten-day simulation. What transfer rate is
required if we are to search this data in ten minutes?
7. Plot the speedup versus number of processors of the prime finding solution for n =
1,000,000, using the data parallel approach, under each of the following scenarios, where is
the time it takes to strike a number, and is the time to pass a number to another processor:
a. = 10
b. = 100
c. = 1000