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After the installation of amd64 etch with generic kernel, I chose a kernel for 
multi dual opteron.
uname -a reports:
Linux debian 2.6.15-1 amd64-k8-smp # SMP

In view of compilation, I I wonder about the following:

Dual (or more) Opteron designs are not SMP (Symmetric Multi Processor), but 
NUMA (Non-Uniform Memory Architecture). With SMP the two CPUs share the same 
bus to memory, but with NUMA each CPU hassome local memory connected to a 
local memory bus. The other CPU can still get to that memory, but it's a bit 
slower. If you would only putin 1x 2GB, you will severely slow down the other 
CPU cause it has to go through the other CPU to do memory accesses. See 
The cpu design may have a bearing for the compilation of programs for 
multiprocessor systems, like mpqc (in the compilation notes, mpqc refers 
to "symmetric multiprocessor", see 

Do smp specified on kernel and NUMA for the opteron characteristics fit 
together? I can imagine that SMP specified on the kernel chosen simply refers 
to the presence of more than one dual-opteron. Anyway, it is a bit confusing 
because it might be seen in conflict with the NUMA characteristics of 

If it is a silly question, I beg pardon.

francesco pietra

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