I'd be very much surprised if there were any significant workloads that would work faster on this thing than on a decently set up Linux or BSD install on the same hardware.
It's not my impression that modern OSs has a habit of getting in the way of pure computation - and when the computation is done, I'd much prefer a solid filesystem/network stack to get the results out of the door.
But as an academic/tinkering/hacking project, it's awesome. If assembly was in my backlog of stuff I want to learn/play with, this would be an obvious thing to get started on.
Cray runs a stripped down kernel they call Compute Node Linux. It still has virtual memory, which combined with the frequency of getting poorly mapped physical pages, causes difficult to predict performance. It is just accepted that performance results are not reproducible on the Cray and most modern clusters, especially those with "fat" nodes. For large runs on Jaguar, the standard deviation is often 20% to 30%, so people who are doing scalability studies run the same model several times and plot the best result. It can be worse on clusters like Ranger (4-socket quad-core Opteron nodes, connected by InfiniBand). Of course running the same 100k core job repeatedly to get a stable timing is a waste of resources. The problem is a combination of VM, multi-core interference, daemon noise, and network topology variability between runs.
In contrast, IBM's Blue Gene series runs Compute Node Kernel which is not Linux and uses offset-mapped memory. This obviates the need for a TLB. The rest of the OS is also stripped down compared to Cray's already lean CNL. Performance variability on Blue Gene is usually reliably less than 1%.
I think BareMetal looks rather silly and will probably not be used for anything serious, but ordinary Linux or BSD is a dubious choice for HPC.
It's not my impression that modern OSs has a habit of getting in the way of pure computation - and when the computation is done, I'd much prefer a solid filesystem/network stack to get the results out of the door.
But as an academic/tinkering/hacking project, it's awesome. If assembly was in my backlog of stuff I want to learn/play with, this would be an obvious thing to get started on.