lkml.org 
[lkml]   [2001]   [Apr]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: X15 alpha release: as fast as TUX but in user space (fwd)
"David S. Miller" wrote:
>
> dean gaudet writes:
> > i was kind of solving a different problem with the code page though -- the
> > ability to use rdtsc on SMP boxes with processors of varying speeds and
> > synchronizations.
>
> A better way to solve that problem is the way UltraSPARC-III do and
> future ia64 systems will, by way of a "system tick" register which
> increments at a constant rate regardless of how the cpus are clocked.
>
> The "system tick" pulse goes into the processor, so it's still a local
> cpu register being accessed. Think of it as a system bus clock cycle
> counter.
>
> Granted, you probably couldn't make changes to the hardware you were
> working on at the time :-)
>

RDTSC in Crusoe processors does basically this.

-hpa

--
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:52    [W:0.355 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site