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

["Blue Swirl" <blauwirbel@gmail.com>]

On 8/24/08, Avi Kivity <avi@qumranet.com> 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.

But on real machines there could be gaps between the memory banks,
memory banks may be of different sizes and then there are aliasing
effects. I doubt you can manage with 20 probes then.

> >  Moreover, this level of precision would not
> > gain anything in Qemu use, it would be unnecessary. If Bochs BIOS was
> > aiming to be used as a real, physical PC BIOS in the future, then
> > these kind of improvements might be useful.
> >
> >
> >
>
>  Agree, it isn't necessary.
>
>
> > A long time ago on Sparc32, I put the memory size to one of CPU
> > registers. That was quick and easy for both sides but dirty.
> >
> >
>
>  For x86 it seems like an obvious candidate for vmport (and I don't
> understand the object to using vmport for uuid).

UUID can be used in all machines, so it would be nice if the interface
was same. I don't see much benefit in vmport compared to ROM solution.