Does hyperthreading still show up as 2 cpu in kernel 2.6.22?

user1qaz2wsx · 03-20-2008, 11:34 AM

I am running a stock install of OpenSuse 10.3 on a Toshiba Satellite A75-S206. It has an Intel P4 hyperthreading processor and when I had Suse 10.2 installed, cpuinfo showed 2 processors. I have tried the acpi=ht and acpismp=force flags on 10.3, but still only one cpu in cpuinfo. How do I enable hyperthreading in OpenSuse 10.3 or is it already enabled and I'm just an idiot?

uname -rv
2.6.22.5-31-default #1 SMP 2007/09/21 22:29:00 UTC

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 3
model name : Mobile Intel(R) Pentium(R) 4 CPU 2.80GHz
stepping : 4
cpu MHz : 1867.000
cache size : 1024 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe constant_tsc up pni monitor ds_cpl est tm2 cid xtpr
bogomips : 5603.67
clflush size : 64

Thanks!

marozsas · 03-20-2008, 02:25 PM

Hi !

Usually, the BIOS has a setup to enable/disable hyperthreading.
Check the BIOS to be sure it is enabled.

emrecio · 06-24-2008, 03:38 PM

The same thing happened to me when I went from F8 to F9. I have not changed anything in the BIOS, and HT is enabled. So I don't understand why I have 1 CPU now instead of 2 CPUs (1 phy w/ 2 HT's).

Is it because I am running an SMP kernel instead of a regular kernel?

farslayer · 06-24-2008, 04:02 PM

possibly you could enable it in the grub menu..

Quote:

Once the installation to install linux-686-smp kernel:
sudo apt-get install linux-686-smp

Then add in menu.list
apci=off ht=on

For example:

Code:

title        Ubuntu, kernel 2.6.17-11-generic-ht 
root        (hd0,7) root 
kernel        /boot/vmlinuz-2.6.17-11-generic root=/dev/sda8 ro apci=off ht=on quiet splash locale=zh_CN 
initrd        /boot/initrd.img-2.6.17-11-generic 
quiet 
boot