[Bridge] stresstest.sh

Stephen Hemminger shemminger at osdl.org
Mon Sep 19 09:34:12 PDT 2005


On Mon, 19 Sep 2005 08:49:22 -0700
Tom McNeal <tmcneal at mvista.com> wrote:

> Stephen Hemminger wrote:
> > On Fri, 16 Sep 2005 14:43:42 -0700
> > Tom McNeal <tmcneal at mvista.com> wrote:
> > 
> >>Hi -
> >>
> >>When running the stress tests, after a few hours, a panic occurs
> >>due to a kernel page fault for address 0x0 while executing one
> >>of the brctl commands.  We don't know which one, yet.  Has anyone
> >>run across this?
> >>
> >>This is basically in the 2.4.17 kernel, with some of the security
> >>fixes.
> >>
> >>Tom
> > 
> > 
> > Some basics:
> > 	* 2.4.17 is pretty old, can you at least try 2.4.30 or later.
> >           Better yet, 2.6
> > 	* Why are you doing bridge commands during the stress test?
> > 	  it is pretty much a setup and forget it thing.
> > 	* are you using SMP?  Locking in bridge code for 2.4 is pretty
> > 	  weak and there are probably holes. I ended up reworking the whole
> > 	  locking model of bridge code for 2.6 for speed and correctness.
> > 
> 
> By 'bridge commands' I meant the brctl command, used by the stress
> tests posted in the bridge-utils-1.0.6 test directory.  The tests
> add and delete bridges while independently adding and deleting
> interfaces to the supposedly existing bridge, in independent loops.
> How real world is that?

It isn't real world at all, but the test was made to make sure
the locking changes for 2.6 (especially switching to RCU), were
safe.

Real world would be blasting lots of packets through (with something
like pktgen), and also testing with 1000's of different source addresses
to make sure forwarding table survives.

> I'm pretty sure it is SMP; are there fixes, like the ones you added
> in 2.4.22 and 2.4.27, which are relevant?  I'm looking at trying to
> patch 2.4.17 right now (I can't upgrade, but I can patch).  I do
> seem some locking stuff that I'm going to look at now....

You probably could just copy whole net/bridge directory over from
current 2.4 tree.




More information about the Bridge mailing list