the 'timer wheel' - which has low resolution works at jiffy resolution. so usually it has precision of 1~10ms. and there's high resolution timers in kernel to have nanosecond resolution, but it doesn't seem to have nanosecond precision is there a way to deal with high precision timers in kernel? does it require specific hardware?
On Sun, May 02, 2021 at 11:10:11PM +0900, Hyeonggon Yoo wrote:
the 'timer wheel' - which has low resolution works at jiffy resolution. so usually it has precision of 1~10ms.
and there's high resolution timers in kernel to have nanosecond resolution, but it doesn't seem to have nanosecond precision
is there a way to deal with high precision timers in kernel?
What exactly are you needing here? And do you have hardware that provides both high precision and high resolution? thanks, greg k-h
I mean, is there an API that guarantees high precision (non architecture dependent way) Thanks! 2021년 5월 2일 (일) 오후 11:54, Greg KH <greg@kroah.com>님이 작성:
On Sun, May 02, 2021 at 11:10:11PM +0900, Hyeonggon Yoo wrote:
the 'timer wheel' - which has low resolution works at jiffy resolution. so usually it has precision of 1~10ms.
and there's high resolution timers in kernel to have nanosecond resolution, but it doesn't seem to have nanosecond precision
is there a way to deal with high precision timers in kernel?
What exactly are you needing here? And do you have hardware that provides both high precision and high resolution?
thanks,
greg k-h
Greg, and Valdis Thank you so much! It helped a lot! I thought there would be a way to do it because of high resolution. 2021년 5월 3일 (월) 오후 8:13, Valdis Klētnieks <valdis.kletnieks@vt.edu>님이 작성:
On Mon, 03 May 2021 00:56:17 +0900, Hyeonggon Yoo said:
I mean, is there an API that guarantees high precision (non architecture dependent way)
How do you guarantee high precision if you're on hardware that doesn't provide a high precision/resolution timer?
Hi On Mon, May 3, 2021 at 2:16 PM Hyeonggon Yoo <42.hyeyoo@gmail.com> wrote:
Greg, and Valdis Thank you so much! It helped a lot!
I thought there would be a way to do it because of high resolution.
2021년 5월 3일 (월) 오후 8:13, Valdis Klētnieks <valdis.kletnieks@vt.edu>님이 작성:
On Mon, 03 May 2021 00:56:17 +0900, Hyeonggon Yoo said:
I mean, is there an API that guarantees high precision (non architecture dependent way)
How do you guarantee high precision if you're on hardware that doesn't provide a high precision/resolution timer?
If you don't have any hardware support, the Linux kernel can't magically count faster than its system tick. ^^
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
participants (4)
-
Greg KH -
Hyeonggon Yoo -
loïc tourlonias -
Valdis Klētnieks