topic Re: RHEL not recognizing dual core CPU's in Operating System - Linux

RHEL not recognizing dual core CPU's

prakasse — Thu, 20 Aug 2009 16:33:02 GMT

Hi Folks,

We have installed RHEL 5.2 on HP rx6600. cat /proc/cpuinfo command says that there are 4 processor. But these processor are dual cores. So totally there are 8 cores.

What command in Linux will tell us that the total number of cores in then system is 8?

Correct answer will be awarded full points.

Thanks,
Senthil.

Re: RHEL not recognizing dual core CPU's

Ivan Ferreira — Thu, 20 Aug 2009 17:36:49 GMT

Can you please post the ouput of:

uname -r
cat /proc/cmdline

Have you started with an SMP kernel enabled?

Re: RHEL not recognizing dual core CPU's

Matti_Kurkela — Thu, 20 Aug 2009 17:41:12 GMT

I think you're a bit hasty in assuming that Linux does not detect the number of cores correctly.

http://www.redhat.com/rhel/compare/

Unless you're running RHEL 5 Advanced Platform, the problem is the number of physical CPUs. To support more than 2 physical CPU sockets, Advanced Platform version is mandatory.

2 physical CPUs allowed x 2 cores each = 4 CPU cores total available to the OS and applications.

Check the system boot messages. If they scrolled by too fast, run "dmesg | less". You may find that the kernel is trying to tell you exactly what the problem is.

MK

Re: RHEL not recognizing dual core CPU's

Zinky — Tue, 25 Aug 2009 15:05:47 GMT

Only Redhat Linux Advanced Server (RHEL AS) supports more than 2 sockets regardless of the number of cores.

That is why we all wait for the Octo-Core Nehalems.

Re: RHEL not recognizing dual core CPU's

prakasse — Tue, 25 Aug 2009 16:00:12 GMT

Thanks.