Re: [Xen-devel] ballon driver interaction with native page allocator.

["Tej Parkash" <tejparkash.d@xxxxxxxxx>]

On 6/8/07, Mark Williamson <mark.williamson@xxxxxxxxxxxx> wrote:
> > if Balloon driver is not present in the guest OS then how xen control
> > the memory of the that Guest OS
>
> It can't; Xen depends on guest OS co-operation in order to resize the guest's
> physical memory footprint.
ok it means if during domU creation if config file says memory is 64MB
then it can't be resize.
> > or there is some other mechanism also with which the guest OS page
> > allocator can inftate or deflate the balloon.
>
> The balloon can be controlled from outside Xen using xm mem-set.  It can also
outside xen means guest OS can use xm-mem set tool to inflate and
deflate the ballon.

> be controlled within the guest by echoing something into a special file.  If
> there's no balloon driver, there's no way to change the memory footprint (as
> of 3.1 the balloon driver can work in HVM, though).
>
> Other hypervisors / virtual machine software is able to page guest memory out
> to disk in order to vary the machine RAM allocation used by each guest; Xen
> doesn't do this.
> Cheers,
> Mark
I think so many control for the ballon driver may cause the conflit if
xen and guest OS is simultaneously trying to resize the ballon.

> --
> Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
> Mark: To answer a question with a question: What use is a skateboard?
> Dave: Skateboards have wheels.
> Mark: My wheel has a wheel!
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel