Re: [PATCH] Make ballooning work with maxmem > mem (i386 version)

["Daniel P. Berrange" <berrange@redhat.com>]

On Fri, Nov 10, 2006 at 03:44:07PM +0000, Keir Fraser wrote:
> 
> 
> 
> On 10/11/06 15:33, "Glauber de Oliveira Costa" <gcosta@redhat.com> wrote:
> 
> >> I took both patches and then changed my mind and immediately reverted them.
> >> There is a better way: we should support the XENMEM_memory_map hypercall.
> >> We should provide a hypercall (domctl) to set a memory_map_limit parameter
> >> and then Xen can use that to fake a memory map when XENMEM_memory_map is
> >> called. The tools can set that parameter from config['maxmem'].
> > 
> > And what happens when the hypercall ever returns ENOSYS, like a kernel
> > running in a bit old Hypervisor?
> 
> Oh, and bear in mind you can always use 'memory=' as a boot parameter to
> force the p2m size and mem_map size.

That's not particuarly helpful when booting a domain with pygrub because
now everytime you change the memory settings in the config for the guest
you also need to update the grub config to actually make it take effect.
Or, if you're not using pygrub, then every time you change the 'mem'
setting in the guest config, you also need to update the 'extra' setting
for the command line.

Regards,
Dan.
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