[olug] Determining cores and sockets on Linux...

[Dan Linder]

On Thu, Nov 20, 2008 at 5:15 PM, Obi-Wan <obiwan at jedi.com> wrote:

> I suppose the version of Linux you're running makes a big difference
> in what cpuinfo reports.  The two problematic work machines I reported
> are running old (2.6.15) and ancient (2.4.32) kernels, respectively.
> If you're running new enough kernels, I still like my suggestion of
> just counting the "core id : 0" lines to compute sockets.


I'm still tracking it down, but it happens that the first test servers I
initially looked at didn't have usable /proc/cpuinfo data (a "Intel(R)
Xeon(TM) CPU 2.66GHz" and "Dual-Core AMD Opteron(tm) Processor 2210 EE").

But my other test servers gave me better data ("Intel(R) Pentium(R) 4 CPU
3.06GHz", "AMD Athlon(tm) 64 X2 Dual Core Processor 6000+", "AMD Phenom(tm)
9550 Quad-Core Processor", "Intel(R) Xeon(R) CPU            5150  @
2.66GHz", and "Intel(R) Xeon(R) CPU 5140 @ 2.33GHz").  From the /proc/cpu
output of these systems, it looks like I can compute #cores and #sockets
this way:


Num_Cores = Number of Unique "core id" entries.
Num_Sockets = Num_Cores / Number of Unique "physical id"

I'll keep working - this doesn't pertain to the first two systems I
mentioned, so I might have to make a small exceptions list.

...but I'm still open to others thoughts! :-)

Dan

-- 
"Quis custodiet ipsos custodes?" (Who can watch the watchmen?) -- from the
Satires of Juvenal
"I do not fear computers, I fear the lack of them." -- Isaac Asimov (Author)
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