Re: Question about cpu time accuracy.

[Jennifer Huang <carrothh@yahoo.com>]

Thanks very much for your information.

Just one more question, does it work for 2.4.18?
Thanks.

--- Kurt Wall <kwall@kurtwerks.com> wrote:
> Scribbling feverishly on May 12, Jennifer Huang
> managed to emit:
> > Hi all,
> > 
> > I have a question about cpu time accuracy.
> > 
> > I am using kernel 2.4.18. But, when I tried
> "utime"
> > and "nanosleep" to get a process suspended, it
> only
> > worked in 10ms granularity, and it's no way to
> sleep
> > for 1 microsecond.
> 
> The standard kernel timer has a resolution of 1/HZ,
> which is 10ms on 
> an x86. You could try a scheduling policy of
> SCHED_FIFO or SCHED_RR,
> but this only gets you 2ms resolution. 
> 
> > Anyone can help me out of this?
> 
> There are patches available for high resolution
> timers:
> 
> http://sourceforge.net/projects/high-res-timers/
> http://www.cs.wisc.edu/paradyn/libhrtime/
> 
> Kurt
> -- 
> Anarchy may not be the best form of government, but
> it's better than no
> government at all.
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