Re: Re: [Xen-devel] VMX Hardware

[Mogens Valentin <monz@danbbs.dk>]

Keir Fraser wrote:
> 
> On 14 Aug 2005, at 11:44, Goetz Bock wrote:
> 
>> As the VMX hardware is supposed to be out "soon" I actually wanted to
>> wait for it to hit the shelvs first.
>>
>> Looks like I can not do this. so I've a question for the informed.
>>
>> What hardware should I get now, and still be able to upgrade to VMX when
>> it's available? If possible only by getting a new CPU.
> 
> 
> Buying a mainboard with LGA775 socket is probably a fairly safe bet, but 
> there's no guarantee that future processor generations will run on it 
> even if the socket doesn't change. Compatibility might depend on the 
> manufacturer creating appropriate BIOS patches, for example.

Looking at Intels latest 'upgrade' path, which shows we'll often have to 
buy new HW for new cpu's, I'd go for AMD.
Seems they're into the game of longtime support, so my bet is that 
you'll be able to outfit quite a lot of the latest mobos with future 
AMD64 cpu's.
This has of late been the case with i.e. their X2 line. Most resent 
mobos can handle those with a BIOS upgrade.
I'd be looking at Iwill, Tyan, Gigabye.

I assume by VMX, you're talking about cpu/hardware with HW-support for 
virtualisation, i.e. Intels Vanderbilt Technology (VT) and AMD' 
Pacifica. If so, it's clear to me that AMD will be leading, because of 
it's onchip memory controller, and hence reduced needs for software 
support to do the page switching, for which Intel needs quite a lot of 
software to emulate.

However, I'm not sufficiently familiar with Xen on this topic (just 
getting started). What I've read is that Xen won't benefit from or even 
use those HW-enabled mechanisms.
Someone pls. correct me if I'm wrong here - I'd very much like to be 
wrong. Would be a pity not to take advantage of such mechanisms, IMHO.

-- 
Kind regards,
Mogens Valentin