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clock () implementation?

Started by jaggu May 4, 2003 at 9:40 PM 1 replies 350+ views

Original Post

May 4, 2003 at 9:40 PM

Hello there, I am trying to find the clock speed of the processor. I use the clock () (time.h) function to let a second elapse, then subtract the values returned thru RDTSC instruction (in assembly) invoked before and after the time interval to find the clocks elapsed. Then I divide this by 1,000,000 to find the clock speed in Mhz. My processor is running at 400Mhz and this program gives values from 397.xxx to 401.xxx. Reasonably accurate. I would like to know how clock () is implemented so that I can get a more accurate value. If you like to see source/exe of my program, please visit: http://www.poojyum.com/jlog/ Thanks. jaggu

jenova

May 4, 2003 at 10:37 PM

if you''re running msvc. you can just step into the clock(); function. it uses GetSystemTimeAsFileTime.

also check google for clock.c to see some linux implementations of the function.

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GoofProg

May 4, 2003 at 10:57 PM

You may want to run your program several times and make an average. This would "smooth" it out a bit.

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