[Discuss] Whence distributed operating systems?

[Rich Pieri]

On 4/28/2016 4:28 AM, Bill Bogstad wrote:
> So memory was shared? between the QBBs?   This sounds more like a NUMA
> architecture environment.  What would you say are the differences
> between this definition
> of SSI and NUMA?

In a NUMA machine, memory is directly attached to the CPUs but not all
of that memory is local to each CPU. Galaxy wasn't NUMA. Each QBB was
NUMA: 4 processors with 512MB local to each with the rest being
non-local but still directly attached. Memory in one QBB was not
directly attached to the processors in other QBBs; it was shared via
software over a fibre data bus.

-- 
Rich P.