Functionality Check

Question

linux gcc 4.4.1 C99

I am wondering what is the best way to test C program performance.

I have some functions that I have implemented. However, I could use a different design for each function.

Basically, I need to check which design gives the best performance.

Many thanks,

Answer 1

You can use gprof, which is a free profiler.

Answer 2

Take a look at this post on code profilers.

Answer 3

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Answer 4

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clock_t t = clock();
for (i = 0; i < 1000; ++i) my_func();
printf("time = %lf\n", (double)(clock() - t) / CLOCKS_PER_SEC);

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Answer 5

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Answer 6

In addition to profiling, you need to run the test code from the harness (driver) to average the readings. Thus, your comparisons are not distorted by a single reading, so you have a large sample with average and standard deviation for comparison. There are many multi-threaded frameworks that can provide load loading.