[Pkg-xen-devel] i386 hypervisor seeing only ~16G RAM, amd64 required?

[Ian Campbell]

On Thu, 2009-01-15 at 00:46 +0000, Andy Smith wrote:
> Hi,
> 
> I have several machines using xen-hypervisor-3.2-1-i386 from
> etch-backports and they recently got upgraded to 20 or 24G RAM.  I
> have seen talk of a limit of a 16G RAM with 32bit PAE Xen and indeed
> this is what I am seeing.
> 
> I am guessing there is still no way to get the 32bit hypervisor to
> see more than 16G RAM, and I must go to 64bit.

Correct, PAE hypervisor can only use 16G of RAM.

> Can I boot a 64bit hypervisor and still keep the same 32bit dom0?
> What're people's experiences running 32bit domUs on
> xen-hypervisor-3.2-1-amd64?

Yes, a 64 bit hypervisor can run both 32 and 64 bit guests, including
dom0, mixed and matched as you like. I run a 32on64 dom0 all the time.

I think you will need a dom0 kernel more recent than the one in Etch to
support guests of a different width to dom0, I'm not sure when exactly
this support was added but Lenny's kernel is certainly OK.

Ian.
-- 
Ian Campbell

BOFH excuse #1:

clock speed
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