[Beowulf] performance tweaks and optimum memory configs for a Nehalem

[Rahul Nabar]

On Sun, Aug 9, 2009 at 9:34 PM, Gus Correa<gus at ldeo.columbia.edu> wrote:
> Most likely it is on.
> Maybe it is the BIOS default, or the vendor set it up this way.
>
> Unfortunately I don't have access to the Nehalem machine.
> So, I can't check the /proc/cpuinfo here, play with MPI, etc.
> I helped a grad student configure it, for his thesis research,
> but the researcher who he works for is a PITA.  Bad politics.

Is there a way of finding out within Linux if Hyperthreading is on or
not? I know there is a BIOS setting but one of the machines I am
testing is remote and I do not have access to BIOS. I'll ask them
though but I am impatient to figure out!

Alternatively /proc/cpuinfo shows a bunch, say 16, cores. Is there a
way to find out if all of these are real cores or hyperthreaded?

-- 
Rahul