Subject: Re: [BUG #12364] Re: HTB - very bad precision? HFSC works fine! 2.6.28

From: Stephen Hemminger <[email-masked]>
Date: Mon, 12 Jan 2009 23:28:11 -0800

On Tue, 13 Jan 2009 05:33:14 +0100
Patrick McHardy <[email-masked]> wrote:

> Denys Fedoryschenko wrote:
> > They are enabled
> > 
> > Router-Dora /config # zcat /proc/config.gz |grep HIGH_RES
> > CONFIG_HIGH_RES_TIMERS=y
> > Router-Dora /config # zcat /proc/config.gz |grep HZ
> > CONFIG_NO_HZ=y
> 
> Its odd that HZ=1000 solved the problem despite HR timers being active.
> Are you sure they're actually enabled? You should see something like
> this in the ringbuffer:
> 
> [    0.241972] Switched to high resolution mode on CPU 0
> [    0.242708] Switched to high resolution mode on CPU 1
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to [email-masked]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Even with NO_HZ the regular kernel won't schedule timers sooner
than HZ. I believe it caused regressions so it was disabled.