Re: [Xen-devel] [PATCH v3 1/3] libxl: xl mem-max et consortes must update static-max in xenstore too

[Ian Jackson <Ian.Jackson@xxxxxxxxxxxxx>]

Daniel Kiper writes ("Re: [Xen-devel] [PATCH v3 1/3] libxl: xl mem-max et 
consortes must update static-max in xenstore too"):
> On Mon, Apr 08, 2013 at 05:21:27PM +0100, Ian Jackson wrote:
> > Doesn't this, together with your previous patch, conflate the "static
> > maximum" (ie, boot-time memory size which in the absence of memory
> > hotplug can never be exceeded), with the "xen maximum" (ie the
> > enforced memory limit) ?
> >
> > I thought that the static-max xenstore key was used for the former.
> 
> To some extent. However, static-max has always a bit larger value
> than "xen maximum". xl uses static-max to enforce limits on guests
> but it is just an info for guest itself. "xen maximum" is a kind
> of hard limit which could not be exceeded and is enforced on guest
> by Xen hypervisor.

The reason for xl using static-max is that in the absence of memory
hotplug, attempting to raise a guest above static-max will not work.
And this check takes effect in xl.

So that's not "enforcing a limit on guests".

Ian.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel