lkml.org 
[lkml]   [2005]   [Jun]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 2.6.12-mm1 boot failure on NUMA box.

* Martin J. Bligh <mbligh@mbligh.org> wrote:

> > - /*
> > - * In the NUMA case we dont use the TSC as they are not
> > - * synchronized across all CPUs.
> > - */
> > -#ifndef CONFIG_NUMA
> > - if (!use_tsc)
> > -#endif
> > + if (!cpu_has_tsc)
> > /* no locking but a rare wrong value is not a big deal */
> > return jiffies_64 * (1000000000 / HZ);
>
> Humpf. That does look dangerous on a NUMA-Q. The TSCs aren't synced,
> and we can't use them .... have to use PIT, whether the CPUs have TSC
> or not.

is the only problem the unsyncedness? That should be fine as far as the
scheduler is concerned. (we compensate for per-CPU drifts)

Ingo
-
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: 2005-06-24 22:00    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site