[Beowulf] bizarre scaling behavior on a Nehalem

[Rahul Nabar]

On Wed, Aug 12, 2009 at 1:02 PM, Craig Tierney<Craig.Tierney at noaa.gov> wrote:
> When you run uname -a you don't get something like:

> [ctierney at wfe7 serial]$ uname -a
> Linux wfe7 2.6.18-128.2.1.el5 #1 SMP Thu Aug 6 02:00:18 GMT 2009 x86_64 x86_64 x86_64 GNU/Linux

uname -a
Linux node25 2.6.18-128.el5 #1 SMP Wed Jan 21 10:41:14 EST 2009 x86_64
x86_64 x86_64 GNU/Linux

So it does seem that yours might be a little newer than mine (the 2.1 suffix?)


>
> We did build our kernel from source, only because we ripped out
> the IB so we could build from the latest OFED stack.

We didn't. We used the latest from the CentOS website.

> Try:
>
> # rpm -qa | grep kernel
>

rpm -qa | grep kernel
kernel-devel-2.6.18-128.el5
kernel-headers-2.6.18-128.el5
kernel-2.6.18-128.el5