The following reply was made to PR port-xen/34005; it has been noted by GNATS.
From: yamt@xxxxxxxxxxxxxxxxx (YAMAMOTO Takashi)
Cc: port-xen-maintainer@xxxxxxxxxx, gnats-admin@xxxxxxxxxx,
Subject: Re: port-xen/34005: xen3 loses bio requests?
Date: Mon, 16 Oct 2006 10:43:33 +0900 (JST)
> On Sat, Jul 15, 2006 at 05:15:00AM +0000, yamt@xxxxxxxxxxxxxxxxx wrote:
> > after switching one of my machines from xen2 to xen3,
> > i occasionally (less frequently than once a day) see lwps in domU
> > stucking in "biowait", "vflushbuf". (and "vnlock").
> > i guess in some cases bio requests get stuck or lost?
> > i haven't successfully checked if it was the whole xbd or just
> > some requests being stuck.
> > - it's a single processor machine.
> > - both of dom0 and domU are netbsd-current.
> > (i haven't noticed the problem on linux domU yet,
> > but it can be a matter of luck.)
> > - it used to work fine with xen2.
> could you try current with these changes:
> cvs rdiff -r1.12 -r1.13 src/sys/arch/xen/include/cpufunc.h
> cvs rdiff -r1.5 -r1.6 src/sys/arch/xen/include/xen3-public/io/ring.h
> It seems to fixe a similar hang in the network interface for me ...
i don't think it can fix the problem for me as it's a single cpu machine.
i can try it later but i don't have a recipe to reproduce the problem yet.