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The results of the SPEC CPU2006 bzip2 benchmark running on an AMD Barcelona has an instruction count of 2.389E12, an execution time of 750 s, and a reference time of 9650 s. 1.12.1 [5] <§§1.6, 1.9> Find the CPI if the clock cycle time is 0.333ns. 1.12.2 [5] <§1.9> Find the SPECratio. 1.12.3 [5] <§§1.6, 1.9> Find the increase in CPU time if the number of instructions of the benchmark is increased by 10% without affecting the CPI.

User Micaela
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Final answer:

The CPI is calculated using execution time, instruction count, and clock cycle time, resulting in a CPI of 0.935 for the AMD Barcelona. The SPEC ratio is found by dividing the reference time by the execution time, yielding a SPEC ratio of 12.867. Lastly, a 10% increase in instructions would affect the CPU time based on the unchanged CPI and clock cycles.

Step-by-step explanation:

Finding the CPI

The CPI (Cycles Per Instruction) can be calculated using the formula CPI = Execution Time / (Instruction Count × Clock Cycle). Given an execution time of 750 seconds, an instruction count of 2.389E12 instructions, and a clock cycle time of 0.333ns, we can calculate the CPI. First, convert the cycle time to seconds by multiplying by 1E-9 (since nanoseconds are 1 billionth of a second). CPI = 750s / (2.389E12 × 0.333E-9s) = 0.935.

Finding the SPEC ratio

The SPEC ratio is a measure of performance compared to a reference machine. It is calculated by dividing the reference time by the execution time. In this case, the SPEC ratio = 9650s / 750s = 12.867.

Calculating the Increase in CPU Time

If the number of instructions increases by 10%, the new instruction count will be 2.389E12 × 1.10. Without affecting the CPI, the new execution time can be found by multiplying the new instruction count by the CPI and the clock cycle. The increase in CPU time will be the difference between the new execution time and the original.

User Maystro
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