FC6 kernels & 4GB of memory

[Wolfgang S. Rupprecht]

Darryl <fedora at idealgroup.com> writes:
> I am setting up a new machine that has 4GB of ECC memory (Smolt UUID
> c0eefda6-6c8f-4663-a9b5-1e1adbcc0fc7) on an Asus M2V mobo (8GB max
> capacity, latest BIOS) with Athlon64 X2 5400+ but can't seem to get
> FC6 to utilize all the available memory. 

To see your memory layout check /proc/mtrr.  Below is what I have for
my 4GB amd64 Tyan 2865 mobo w. 64-bit kernel: It took quite a bit of
playing with the Tyan bios to get it to set up the address maps
correctly.  There were three unhelpfully labeled entries that
interacted.

  reset to factory "optimized" settings.
  select mtrr discontinuous		  (was contigious)
  select mtrr hardware mapping		  (was disabled)
  select iommu 128k		          (was disabled)
  (others left at factory default)

# cat /proc/mtrr
reg00: base=0x00000000 (   0MB), size=2048MB: write-back, count=1
reg01: base=0x80000000 (2048MB), size=1024MB: write-back, count=1
reg02: base=0xc0000000 (3072MB), size= 256MB: write-back, count=1
reg03: base=0xcff00000 (3327MB), size=   1MB: uncachable, count=1
reg04: base=0x100000000 (4096MB), size= 512MB: write-back, count=1
reg05: base=0x120000000 (4608MB), size= 256MB: write-back, count=1
reg06: base=0xd8000000 (3456MB), size= 128MB: write-combining, count=2

Maybe your board ha a bunch of settings you need to ferret out too?

-wolfgang
-- 
Wolfgang S. Rupprecht                http://www.wsrcc.com/wolfgang/