Re: [Qemu-devel] [PATCH 0/6] Add UUID command-line option

[Kevin O'Connor]

On Sun, Aug 24, 2008 at 04:55:44PM +0300, Avi Kivity wrote:
> Blue Swirl wrote:
>> True, but realistic probing for memory could take some time if there
>> is a huge amount of it.
>
> No reason for that.  A binary search with a cap of 1TB and a granularity  
> of 1MB requires only 20 probes.

Real x86 machines detect the available memory chips via the smbus and
then program the memory controller.  The initialization code must do
this work without accessing any memory.  The coreboot project
(coreboot.org) has more info if you're interested.

-Kevin