> On Mon, Sep 8, 2008 at 10:46 PM, David Miller <davem@davemloft.net> wrote:
> > From: Stephen Hemminger <shemminger@vyatta.com>
> > Date: Thu, 4 Sep 2008 15:47:09 -0700
> >
> >> The bridge hello time can't be safely set to values less than 1 second,
> >> otherwise it is possible to end up with a runaway timer.
> >>
> >> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
> >
> > Applied, thanks Stephen.
> >
> > I added more information to the commit message so that Dushan's
> > incredibly contribution to this bug getting fixed are mentioned.
> > I don't see how we would have figured out Bridging as even the
> > cause without his detective work. So it's definitely wrong not
> > to give him at least some mention in the commit message :-/
> >
>
> I don't know what to say :)
>
> Thank you
> > bridge: don't allow setting hello time to zero
> >
> > Dushan Tcholich reports that on his system ksoftirqd can consume
> > between %6 to %10 of cpu time, and cause ~200 context switches per
> > second.
> >
> A little nitpick: 200 times greater context switch rate :), like
> 100000 per second.
>
> > He then correlated this with a report by bdupree@techfinesse.com:
> >
> >
http://marc.info/?l=linux-kernel&m=119613299024398&w=2
> >
> > and the culprit cause seems to be starting the bridge interface.
> > In particular, when starting the bridge interface, his scripts
> > are specifying a hello timer interval of "0".
> >
> > The bridge hello time can't be safely set to values less than 1
> > second, otherwise it is possible to end up with a runaway timer.
>
> Btw. is there a way to make the command to turn STP off work too?
> brctl stp br0 off
> Because AFAIK if I shut down STP the hello timer should shut down too,
> but it still continues to work.
>
> Thank you for your time and effort
>
> Dushan Tcholich
>
