Solved

Measure execution cycles of a code..

Posted on 2000-03-10
7
356 Views
Last Modified: 2013-11-15
I am now writing a code in C.
I want to measure execution speed of a code for as high resolution as possible.
I've tried to read PC timer (mc146818) datasheet, its registers can only give 1 second resolution.
Interrupt 1A can only gives 1/100 second resolution.
If it is possible, I want to get the result as a number of clock cycles.
Anybody can point me out about this?

Thanks,
0
Comment
Question by:wayud
7 Comments
 
LVL 11

Expert Comment

by:alexo
ID: 2604570
If you program under windows, check the following functions:
  QueryPerformanceCounter()
  QueryPerformanceFrequency()

0
 
LVL 11

Accepted Solution

by:
alexo earned 100 total points
ID: 2604604
Otherwise, there are pentium-specific instructions that you may use to get high resolution timing.
Check RDTSC
0
 
LVL 3

Expert Comment

by:3rsrichard
ID: 2604729
I can suggest two possible solutions
1) If you can run your program on a machine using Windows NT you can use the Administrative Tools - Performance Monitor to get something related to what you want.

The problem with trying to use the hardware timers is that the answer you get will be based on a specific set of hardware.  Another approach is to compile the code, get a listing, and count the number of instructions being executed.  Or if you have a debugger which keeps track of the number of lines executed that would do it.
0
Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 31

Expert Comment

by:Zoppo
ID: 2604951
Hi wayud,

Have you tried 'clock'? It's resolution seems to be at least 20ms. Use it like this:

#include <time.h>

clock_t end, start = clock();
// do lengthy processing
end = clock();

hope that helps,

ZOPPO
0
 
LVL 5

Expert Comment

by:Wyn
ID: 2605210
->If you program under windows, check the following functions:
  QueryPerformanceCounter()
  QueryPerformanceFrequency()
=================================
Fully agree.
0
 
LVL 32

Expert Comment

by:jhance
ID: 2605249
Another approach is to run the instructions in question 10, 100, 1000, etc. times (whatever is needed to get a meaningful result with the timer available) and then scale the result.
0
 

Author Comment

by:wayud
ID: 2606973
Thank you for all of you..
This is what I really need.
I'll try it now.
0

Featured Post

Back Up Your Microsoft Windows Server®

Back up all your Microsoft Windows Server – on-premises, in remote locations, in private and hybrid clouds. Your entire Windows Server will be backed up in one easy step with patented, block-level disk imaging. We achieve RTOs (recovery time objectives) as low as 15 seconds.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A high-level exploration of how our ever-increasing access to information has changed the way we do our jobs.
In this article, you will read about the trends across the human resources departments for the upcoming year. Some of them include improving employee experience, adopting new technologies, using HR software to its full extent, and integrating artifi…
The goal of this video is to provide viewers with basic examples to understand how to create, access, and change arrays in the C programming language.
Viewers will learn how to use the Hootsuite Dashboard.

733 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question