Re: lost memory on a 4GB amd64

[Rafael J. Wysocki]

On Friday 24 of September 2004 10:57, Sergei Haller wrote:
> On Fri, 24 Sep 2004, Andrew Walrond (AW) wrote:
> 
> AW> On Friday 24 Sep 2004 09:23, Sergei Haller wrote:
> AW> > It's the same for me if I use the non-SMP version of the kernel.
> AW> > but the SMP one seems to be panicking for some reason.
> AW> >
> AW> 
> AW> Just a thought; How are the memory modules arranged on the board?
> AW> I have 2 x 1Gb modules in each cpu-specific bank, rather than all four 
in 
> AW> cpu1's bank. How are yours arranged?
> 
> my board has only four banks, each of them has a 1GB module sitting.
> (page 26 of ftp://ftp.tyan.com/manuals/m_s2875_102.pdf)

Which is what makes the difference, I think.  IMO, the problem is that _both_ 
CPUs use the same memory bank that is physically attached to only one of them 
which leads to conflicts, apparently (the CPU with memory has also 
PCI/AGP/whatever attached to it via HyperTransport so I can imagine there may 
be issues with overlapping address spaces etc.).  I'd bet that there's 
something wrong either with the BIOS or with the board design itself and I 
don't think there's anything that the kernel can do about it (usual 
disclaimer applies).

Out of couriosity: have you tried to run the kernel with K8 NUMA enabled?

Greets,
RJW

-- 
- Would you tell me, please, which way I ought to go from here?
- That depends a good deal on where you want to get to.
		-- Lewis Carroll "Alice's Adventures in Wonderland"
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