[Fedora-xen] Memory in xen kernel < physical memory

[Thorsten Leemhuis]

Am Mittwoch, den 22.02.2006, 14:31 -0600 schrieb Steven Pritchard:
> On Wed, Feb 22, 2006 at 12:28:09PM -0800, Ben wrote:
> > I thought PAE was only for 32 bit machine? I've got a 64-bit opteron  
> > and also noticed that the FC5t3 hypervisor kernel doesn't show all  
> > 4GB of my RAM.
> 
> A lot of Athlon64 boards only seem to support 3.5GB,

Most with Socket 939 support 4 GByte afaics.

>  like the old
> Athlon MP boards.  I haven't every been given a good reason why...

PCI-Address-Space just below 4 GByte needs around 0,25 up to round about
0,75 MByte normally (depending on PCI/PCIe/AGP devices you have
installed).

But most newer Mailboards support "Memory-Hoisting" (needs Rev. E Athons
iirc). Enable it in the BIOS and use a 64-Bit-Operating-System to access
the complete 4**GByte of memory. 
-- 
Thorsten Leemhuis <fedora at leemhuis.info>