[lkml]   [2006]   [Jun]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Network performance degradation from to

Jesper Dangaard Brouer wrote:
>>> Harry Edmon <> wrote:
>>>> I have a system with a strange network performance degradation from
>>>> to most recent kernels including and
>>>> 2.6.17-rc6. The system is has Dual single core Xeons with
>>>> hyperthreading on.
> <cut>
> Hi Harry
> Can you check which "high-res timesource" you are using?
> In the kernel log look for:
> kernel: Using tsc for high-res timesource
> kernel: Using pmtmr for high-res timesource
> I have experinced some network performance degradation when using the
> "pmtmr" timesource, on a Opteron AMD system. It seems that the
> default timesource change between 2.6.15 to 2.6.16.
> If you use "pmtmr" try to reboot with kernel option "clock=tsc".
> On my Opteron AMD system i normally can route 400 kpps, but with
> timesource "pmtmr" i could only route around 83 kpps. (I found the
> timer to be the issue by using oprofile).
We have CONFIG_HPET_TIMER=y, so we do not see these messages.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2006-06-19 18:43    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean