[JonWoodruff]

Coïncidence or not, CNet reports that

"Microsoft is building a high-end feature into Windows for speeding up data access in multiprocessor servers--a feature that to date has been available only in high-end Unix servers, the company said Tuesday. "
The Redmond, Wash.-based software company is working on support for a technology called non-uniform memory access, or NUMA, one method for designing large servers crammed with processors, said Sean McGrane, program manager for Microsoft's top-end Datacenter server.

That's from AcesHardware.com.

AMD's Hammer processors use a NUMA architecture for mult-processing, where each processor has it's own bank of memory and is connected to the other processors with their own banks of memory through a chain or network of point-to-point busses. Problem with that is that if all the memory appears as one big chunk to the OS (which it does), half the time, or a quarter of the time each processor will be fetching data through the other processor's memory controllers over the point-to-point network. (HyperTransport in Hammer's case)

AMD has said (noted on AcesHardware) that OS support for the NUMA archetecture was possible and even necissary, and if Microsoft is supporting AMD then they must be designing a "NUMA controllor" into the Windows memory interface. Why is this significant? Whith a very good design, which Microsoft will have the freedom to do, they will be able to keep the data for each processor's threads in it's own memory bank yeilding near perfect scaling all the way up to lots of processors.

Seems to me that this would be Microsoft's big oppurtunity to penetrate SUN's market for big multi-processor servers, if we don't count Itanium. It will also greatly benefit AMD in the corporate segment. As far as I know, Intel doesn't have anything that gives Microsoft so much scaleability and control over system archetecture. If Microsoft jumps on x86-64 and Hammer with NUMA big time, AMD will benefit big time.