SGI: Hardware

Hi,

For a summer project I was thinking of connecting my two O2000 racks with my two O2000 desksides. This would get me a 48 cpu setup.
I have collected 24 directory ram modules to install for the first memorybank on each nodeboard. This would make the first memorybank appear as 'premium' in hinv (I think).
I assume that bank will be available for the whole setup.

What will happen with memory in the other banks? Will it just be available within a module? Must I remove all memory that don't have directory ram?

Hopefully the craylink cables from O200 will work with the O2000 as well, otherwise I will have to do some shopping.

Origin 200 and Origin 2000 cables are electrically equivalent, the only difference is the stiffer "conduit" on the O200 cables (these cables are sold on the O2000 as Crosstown cables).

AFAIK you need to have expanded directory memory for all installed memory banks on O2k for it to work in large CPU setups. The directory memory allows the O2000 to keep track of where in the global space things are, and if you have too many nodes it overflows the space on the standard DIMMs. I'm not even sure it would be possible for a NUMA system to have private local memory - sort of defeats the purpose .