Kernel SMP

English Install/Boot/Login
1

Hello,

I run my system under Opensuse 11 X64

I wound like to know how can i verify that i’m using SMP with the kernel.
And, if this is not the case, how can i solve it.

Thanks a lot

2

uname -a

if you see SMP in there, then you’re using a SMP-aware kernel

3

thanks

but after, if SMP is not indicated, how to make a SMP-based kernel?

4

you will have to reconfigure and recompile the kernel. There is no need to do such thing since SUSE provides SMP-aware kernels which you can install

5
  • jeromenowe wrote, On 11/11/2008 05:26 PM:
    > thanks
    >
    > but after, if SMP is not indicated, how to make a SMP-based kernel?
    >
    >
    Both the default and the PAE kernel use multiple CPUs/cores these days.

Uwe

6

I don’t understand.

I’ved had a unique core processor. I’ved upgraded to dual core processor.

Will OpenSuse 11.2 use the second core ?

The “uname -a” command doesn’t return SMP.

How to know if the second core is used ?

7

The usual kernel will automatically use SMP processors, no need for a separate -smp kernel any more. If you do

cat /proc/cpuinfo

you will see info on 2 cores.

8

The kernel patches itself for uni-processor & SMP operation, using alternatives code, so same kernel optimises itself depending on your configuration.

The kernel tells you, how many processors it sees, in the file /proc/cpuinfo

fir:/etc # cat /proc/cpuinfo | egrep ‘processor|vendor|physical|siblings|core’
processor : 0
vendor_id : AuthenticAMD
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
address sizes : 40 bits physical, 48 bits virtual
processor : 1
vendor_id : AuthenticAMD
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
address sizes : 40 bits physical, 48 bits virtual

If you see only 1 processor, it may well be a BIOS issue. I have had upgraded BIOSes not being recognised by old kernels, or newer kernels requiring fixed BIOSes.