Strange problem with 8-stable, VMWare vSphere 4 & AMD CPUs (unexpected shutdowns)

[Jeremy Chadwick]

On Wed, Feb 10, 2010 at 07:38:37PM +0100, Ivan Voras wrote:
> On 10 February 2010 19:35, Andriy Gapon <avg at icyb.net.ua> wrote:
> > on 10/02/2010 20:26 Ivan Voras said the following:
> >> On 10 February 2010 19:10, Andriy Gapon <avg at icyb.net.ua> wrote:
> >>> on 10/02/2010 20:03 Ivan Voras said the following:
> >>>> When you say "very unique" is it in the "it is not Linux or Windows"
> >>>> sense or do we do something nonstandard?
> >>> The former - neither Linux, Windows or OpenSolaris seem to have what we have.
> >>
> >> I can't find the exact documents but I think both Windows
> >> MegaUltimateServer (the highest priced version of Windows Server,
> >> whatever it's called today) and Linux (though disabled and marked
> >> Experimental) have it, or have some kind of support for large pages
> >> that might not be as pervasive (maybe they use it for kernel only?). I
> >> have no idea about (Open)Solaris.
> >
> > I haven't said that those OSes do not use large pages.
> > I've said what I've said :-)
> 
> Ok :)
> 
> Is there a difference between "large pages" as they are commonly known
> and "superpages" as in FreeBSD ? In other words - are you referencing
> some specific mechanism, like automatic promotion / demotion of the
> large pages or maybe something else?

I read what Andriy wrote to mean that the way FreeBSD utilises 4MB TLB
on certain models of AMD processors is broken/quirky, and on those CPUs,
users should stick to vm.pmap.pg_ps_enabled="0" (loader.conf).

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |