[KaiserPro]

Its very much commercial linux, because you are paying for a service, that's linux based.

Sure with how cheap inifiband is (especially compared to 40/100 gig ethernet) one _could_ cobble together a system your self.

Where the magic sauce comes in, and where the like of cray really make things shine is the software they provide to allow end users _easily_ do multi-machine scaling.

libraries for just in time delivery of data directly into ram? yup. location aware job dispatchers that co-locate jobs near each other logically? yup.

All of those hard things are solved for you.

[smilesnd]

Redhat is a commercial linux because they are competing with other os/distro in this market. If I pay Joe $5 a month to keep my ubuntu up to date it doesn't make ubuntu a commercial linux even though I am paying for a linux service. These companies building supercomputers are competing in producing supercomputers. Not in providing a linux disto and providing a service for said linux. I very much doubt I could get access to their linux disto and linux service without first purchasing a supercomputer from them.

[nl]

This is pretty much exactly how every HPC OS has been sold since the Cray X-MP. It's like if you buy Isilon - it is a software, hardware and support you buy. No one argues that isn't commercial.