Re: dom0 not seeing all of the assigned memory

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Sun, Mar 11, 2012 at 11:20:02PM +0100, Sven Köhler wrote:
> Am 27.02.2012 20:04, schrieb Roderick Colenbrander:
> > On Mon, Feb 27, 2012 at 5:34 PM, Henrik Olsson <henrik@fixme.se> wrote:
> >> On Thu, Feb 23, 2012 at 19:55, David Vrabel <dvrabel@cantab.net> wrote:
> >>> On 22/02/12 22:19, Henrik Olsson wrote:
> >>>> Hi, i'm having some trouble with assigning memory to my dom0.
> >>>>
> >>>> I've added "dom0_mem=8192M" to the xen command line yet "free -m"
> >>>> reports only 5686MB total.
> >>>
> >>> [    0.000000] Freeing  6f000-100000 pfn range: 593920 pages freed
> >>> [    0.000000] 1-1 mapping on 6f000->100000
> >>> [    0.000000] Released 595312 pages of unused memory
> >>>
> >>> This accounts for most of your "missing" memory.  To get it back you
> >>> need to adjust the balloon driver's target to the amount of memory you want.
> >>>
> >>> David
> >>
> >> Hi, i'm not sure i understand..
> >>
> >> I've configured /etc/xen/xend-config.sxp with:
> >> (dom0-min-mem 8192)
> >> (enable-dom0-ballooning no)
> >>
> >> Shouldn't this disable ballooning? Or do i need to pass some parameter
> >> somewhere?
> 
> I have the same problem. I believe this also happens even if the
> ballooning driver is disabled in dom0 kernel.
> 
> >> Regards,
> >> Henrik
> > 
> > Make sure you have added the following patch to your Xen if you are
> > using a recent >=3.1 kernel. Unfortunately it isn't in Xen 4.1.x, but
> > I guess it should be added to there:
> > http://xenbits.xen.org/hg/staging/xen-unstable.hg/rev/c56dd5eb0fa2
> > 
> > See if it helps.
> 
> I recompiled the hypervisor (this was a patch for the hypervisor,
> right?) and dom0 only has around 413MB inspite of dom0_mem=512M
> hypervisor parameter.
> 
> free shows 413MB straight after booting into dom0 (no xend, xenstored or
> anything xen related stuff has started yet).

<sigh> So it sounds like that the kernel should balloon up the released
amount of memory. David, did we discuss this at some point and agreed that
was the proper way?