Re: cpufreq affects traffic control rates

From: DervishD
Date: Wed Aug 29 2007 - 03:59:53 EST


Hi Stephen :)

* Stephen Hemminger <shemminger@xxxxxxxxxxxxxxxxxxxx> dixit:
> On Tue, 28 Aug 2007 09:51:55 +0200 DervishD <lkml@xxxxxxxxxxxx>
> wrote:
> > I noticed lately that my traffic control rates were being very
> > slow, about 40% less than expected, and finally spotted the
> > problem: cpufreq.
>
> Is the problem configuration of network scheduler clock? In 2.6.20 and
> earlier, you could use CPU cycle counter (later kernels only use time
> of day). So try switching to jiffies or gettimeofday.

Yes, the problem is that I'm stupid and I thought I was using
jiffies, but I have CONFIG_NET_SCH_CLK_CPU. I'll rebuild my kernel ASAP
and set the proper value...

Thanks for your help. It's embarrassing I didn't check the clock
source for the packet scheduler...

Sorry for the noise.

Raúl Núñez de Arenas Coronado

--
Linux Registered User 88736 | http://www.dervishd.net
It's my PC and I'll cry if I want to... RAmen!
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