Example from Sean Peisert's talk at NPACI Parallel Computing Institute 2000
Given:
- A machine's processors run at 222 MHz (as do the Power3 chips on the IBM Blue Horizon).
- Code takes 17 microseconds to run, as determined by, say, gettimeofday().
- A loop consists of 2220 iterations.
222 MHz = 222 x 10^6 cycles per second
17 microseconds = 17 x 10^-6 seconds
(222 * 10^6 cycles/second) * (17 * 10^-6 cycles/second)
---------------------------------------------------------------
2220 iterations
= 1.7 cycles/iteration