Second CPU not recognized

I’ve been searching for a while and clearly must have my terminology in a big mess when it comes to the whole CPU / Processor / Core thing but in any case.

I am running a Dell precision T7600 box with 2 Intel Xeon chips, that’s dual 8 core chips. For whatever reason I can’t seem to get the other to show up.

I’ve run the various commands that check if it sees the second chip.

I booted on my windows partition, and that sees all 16 cores. I even thought I might have messed something up in the bios when I turned off hyperthreading but that seems to be of zero help. (32 cores show up when I am in windows but still no luck in linux with hyperthreading enabled). My BIOS shows 2 8 core processors, pretty much everywhere except linux…

I’ve tried a command along the lines of acpi=off.

I am unfortunately tired and out of ideas of what it could possibly be. Does anyone have any recommendations for me? I am running opensuse 12.2

On 2013-02-14 03:16, A gerb wrote:
> I’ve tried a command along the lines of acpi=off.

But IIRC that disables the cores…


Cheers / Saludos,

Carlos E. R.
(from 12.1 x86_64 “Asparagus” at Telcontar)

A few things that may be interesting:

Code:

cat /proc/cpuinfo

This should get a bunch of information about your CPUs in a big text
format. Paste the output here or in something like SUSE Paste in case
that helps: http://paste.opensuse.org/

Seeing the startup messages may also be interesting:

Code:

dmesg | grep -i proces

Getting all of the ‘dmesg’ output may be important, but this particular
combination gets some interesting information from the start on my system:

Good luck.

The info I got for those two commands are seen here:

SUSE Paste

SUSE Paste

As you can see it only acknowledges that I have 1 eight core processor…

Thoughts?

Which kernel are you using? Post the output from ‘uname -a’; the default
is probably ‘desktop’ and I think that’d be fine, but maybe you’ll need
‘default’ for this instead… just wildly guessing though.

Good luck.

Output for uname -a

Linux kumamotojo 3.1.10-1.16-desktop #1 SMP PREEMPT Wed Jun 27 05:21:40 UTC 2012 (d016078) x86_64 x86_64 x86_64 GNU/Linux

so it is desktop.

On 2013-02-14 17:16, A gerb wrote:
>
> Output for uname -a
>
> Linux kumamotojo 3.1.10-1.16-desktop #1 SMP PREEMPT Wed Jun 27 05:21:40
> UTC 2012 (d016078) x86_64 x86_64 x86_64 GNU/Linux
>
>
> so it is desktop.

Are you booting with the failsafe option, perhaps?


Cheers / Saludos,

Carlos E. R.
(from 12.1 x86_64 “Asparagus” at Telcontar)

No luck there, not booting in failsafe.

I tried various different boots, failsafe, a different desktop, tried running vanilla, all of it was to no avail. I am pretty confused by this. is there a way I can check that the computer knows there’s at least 2 sockets?

maybe dl and run the 12.2 lived and see if both show or install a newer kernel

On 2013-02-15 00:36, A gerb wrote:
> I tried various different boots, failsafe, a different desktop, tried

Failsafe and some other options disable all but one cpu core.


Cheers / Saludos,

Carlos E. R.
(from 12.1 x86_64 “Asparagus” at Telcontar)

On Thu 14 Feb 2013 11:36:01 PM CST, A gerb wrote:

I tried various different boots, failsafe, a different desktop, tried
running vanilla, all of it was to no avail. I am pretty confused by
this. is there a way I can check that the computer knows there’s at
least 2 sockets?

Hi
What exists down in /sys/devices/system/cpu do you see the cpu appear
anywhere in the dmesg output?


Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.28-2.20-desktop
up 10:36, 3 users, load average: 0.04, 0.04, 0.05
CPU Intel® i5 CPU M520@2.40GHz | GPU Intel® Ironlake Mobile

On 02/15/2013 12:36 AM, A gerb wrote:
> is there a way I can check that the computer knows there’s at
> least 2 sockets?

if there is a VM involved, where does it fit in (and what OS is it
running in?) if a VM or other OS is involved, then what happens if
you boot directly from an openSUSE Live CD?

if no VM is in the mix: this could be a bug in openSUSE maybe…i
think i’d try to boot from a Live CD of a different flavor (i would
prefer Knoppix, but any will do and since the machine is certified
for Red Hat 5.7 64, i think i’d try that, if it has a Live CD) and
see if you can duplicate this problem…

if you find that a different version of Linux works ok, then
determine which kernel it is running, and write a bug (to bugzilla)
against yours…

other thoughts:

do you have the user manual which came with the machine? does it have
information on the BIOS setup particular to Linux (the machine is
certified for Red Hat)?

have you checked at the manufactures web site for
infomation/instructions [maybe this is a known problem with a
manufacturer’s suggested fix]? maybe that fix is in a BIOS upgrade?


dd
openSUSE®, the “German Engineered Automobile” of operating systems!
http://tinyurl.com/DD-Caveat

Sorry for the long delay, I just went away for a bit.

So checking in yast, the system sees that there is a second cpu under the bios information (from linux) but the cpu section doesn’t have the second cpu present. the machine itself is Dell T7600 so it does support red hat linux, I’ll have to give that shot first. Seems to me that it would be an OS issue since windows sees the second CPU just fine.

On 02/21/2013 02:56 PM, A gerb wrote:
>
> Sorry for the long delay, I just went away for a bit.
>
> So checking in yast, the system sees that there is a second cpu under
> the bios information (from linux) but the cpu section doesn’t have the
> second cpu present. the machine itself is Dell T7600 so it does support
> red hat linux, I’ll have to give that shot first. Seems to me that it
> would be an OS issue since windows sees the second CPU just fine.

Not an OS issue as much as a kernel issue. I would expect the same behavior for
a given kernel on all distros.

good news and bad news, just ran fail safe mode again after dealing with some other issues… all 16 cores present… ideas?

just tried all the different boot options individually, along with all except for x11failsafe from the grub, and none of it worked, so my guess is it’s either very selective or all of them from failsafe mode need to be activated in order to work…

issue resolved, I don’t understand why but I’ll explain anyway and how I went about finding out.

I checked the /var/log/warn file to see what was happening at boot (unorthodox i’m sure) noticed that post CPU check it stated pci when 8 were being turned on and acpi when 16 were being turned on. used the command acpi=force at the grub, and now all 16 show up…

Pure luck… but a solution. If someone gets wise out of this, great. but otherwise thanks for all the help.