Re: [Qemu-devel] Merging improvements from VirtualBox OSE into qemu?

[Avi Kivity]

Jamie Lokier wrote:
> Paul Brook wrote:
>   
> > Any hardware that supports KVM is already 64-bit, and you're almost
> > entirely targetting obsolete hardware.
> >     
>
> 32-bit hardware is still in use.  My laptop is just over 2 years old,
> and there were *no* 64-bit Intel laptop CPUs available when I bought
> it (or I would have bought one).
>
> I use 32-bit KVM very often on my laptop, for OS compatibility
> testing, Windows development, BSD development, old Linux development
> and binary software packaging.
>
> (I also use QEMU, with and without KQEMU, to run older guest OSes that
> KVM does not work for.)
>
> To say 32-bit KVM-capable hardware is obsolete implies all _relevant_
> laptop users buy new ones every less than 2 years, which sounds
> ridiculous to me.
>
>   

Well, your laptop won't run 64-bit guests at native speeds.  The 
VirtualBox hack requires 64-bit capable hardware, more than likely.  It 
just allows you to run a 32-bit host OS.

If you do have 64-bit capable hardware, then nothing prevents you from 
running a 64-bit host OS (still capable of running 32-bit apps) or a 
64-bit kernel and 32-bit userspace.  The VirtualBox trick is mostly 
relevant to Windows, where 32-bit is still much more popular than 64-bit.

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