On Wed, Jul 25, 2012, Nadav Har'El wrote about "High-resolution user/system times?": > I'm now trying to measure a process running around 3 milliseconds, less > than one jiffy, and I still want to understand how much of it is spent in > user space, and how much of it is spent in kernel space (e.g., handling on
Thanks for all the ideas. I think I found an even simpler solution: It appears that while times(2) has a 4-ms resolution, it doesn't mean that every time a 3-ms process is measured it returns 0. Rather, it seems probabilistic - the user-space count seems (but I didn't verify in the code...) to return 0 if the timer interrupt happened while the code was in the kernel or 1 if the code was in user space. So what I can do is to run the whole process 1,000 times, and add up the "1" and "0"s which I get for system time, and if I get for example 30, I know that the process was in the kernel for 30/1000 of the time. I no idea how accurate this will be, but it might just work, and is very simple... -- Nadav Har'El | Wednesday, Jul 25 2012, 6 Av 5772 [email protected] |----------------------------------------- Phone +972-523-790466, ICQ 13349191 |Wear short sleeves! Support your right to http://nadav.harel.org.il |bare arms! _______________________________________________ Linux-il mailing list [email protected] http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
