Assessment Item J3 – CPU Performance Analysis – CS 310 Computer Architecture
Skill being assessed: Use the CPU performance equation and MIPS rating to compare
the performance of different processors for the same ISA
Program outcome to which this skill is mapped: (j) An ability to apply mathematical
foundations, algorithmic principles, and computer science theory in the modeling
and design of computer-based systems in a way that demonstrates comprehension
of the tradeoffs involved in design choices
Performance Assessment Abstract:
Given the clock rate of two processors that implement the same ISA, the instruction
mix and the CPI for each instruction class, the student is asked to:
1. Compute the average CPI for each processor
2. Compute the MIPS rating of each processor
3. Establish which processor is faster for this instruction mix by computing the
CPU execution time per instruction and the relative performance increase
Rubric for Evaluation
Criteria
CPI
computation
Exemplary
Student wrote
down the
correct
formula and
the correct
final result.
Satisfactory
Student wrote down
the correct formula
but made a small
computational error
after plugging in the
numbers.
MIPS rating
Student wrote
down the
correct
formula and
the correct
MIPS rating.
Instruction
execution
time and
relative
performance
increase
Student wrote
down the
correct
formula and
value for the
execution time
and the
relative
performance
increase.
Student wrote down
the correct formula
but made a small
computational error
after plugging in the
numbers (e.g., did
not divide by 1000)
or did not simplify
the final fraction.
Student wrote down
the correct formulas
and values but their
answer has a minor
flaw (e.g., missing
units or forgot to
state which machine
is faster).
Marginal
Student wrote a slightly
flawed formula of the
weighted sum (e.g.,
unnecessarily divided
the weighted sum by
the number of
instruction classes)
Student wrote down an
incorrect formula and
an incorrect value or
wrote down the correct
value but no formula.
Deficient
Student wrote
down the
wrong answer
with little or no
work shown.
Student wrote the
wrong formula or
reached the wrong
conclusion or used the
wrong units.
Student left out
one of the
answers
altogether, that
is, the
execution time
formula or the
value or the
ratio.
Student did not
include a
formula at all
and the final
numerical
value is either
missing or
wrong.