Lylepalooza
September 11th, 2007, 11:52 AM
I have read in several places about some people having issues with hyper threading in Ubuntu 7.04 Feisty Fawn. Many people have stated that although:
Their CPU/Motherboard are both capable of hyper threading
They have the i686 SMP kernel
They have hyperthreading switched on
There CPU still isn't recognised as being Hyperthreaded IE:
It doesn't appear as two CPU's in system monitor
It doesn't appear as two CPUs if you use the Top command (followed by pressing 1) in terminal
It doesn't appear as two CPUs under the command cat /proc/cpuinfo in terminal
I struggled with the same issue attempting to get my CPU's hyper-threading to work. Eventually the solution was to remove "nopic nolapic" from one of the options in the grub boot menu. In my case, I can't remember why I needed to disable apic in the first place and removing these two words didn't affect my setup at all. However, there may be a very good reason why you did and removing these two words may have undesirable affects on your setup, so be warned.
The grub boot menu can be edited via:
Sudo gedit /boot/grub/menu.lst
The lines you're looking for are similar to:
## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash noapic nolapic
After editing this, hit save, and in terminal type:
Sudo update-grub
After a restart, you should be in business.
For me, this worked perfectly and now I am enjoying the speed boost of hyper-threading.
Now I know the above would seem obvious to some, but to me (a noob) it wasn't. So as you want users to help other users, I thought I would put this short How To together. Moderators, feel free to move it to where ever it should go if it doesn't belong in this category.
Lylepalooza
Their CPU/Motherboard are both capable of hyper threading
They have the i686 SMP kernel
They have hyperthreading switched on
There CPU still isn't recognised as being Hyperthreaded IE:
It doesn't appear as two CPU's in system monitor
It doesn't appear as two CPUs if you use the Top command (followed by pressing 1) in terminal
It doesn't appear as two CPUs under the command cat /proc/cpuinfo in terminal
I struggled with the same issue attempting to get my CPU's hyper-threading to work. Eventually the solution was to remove "nopic nolapic" from one of the options in the grub boot menu. In my case, I can't remember why I needed to disable apic in the first place and removing these two words didn't affect my setup at all. However, there may be a very good reason why you did and removing these two words may have undesirable affects on your setup, so be warned.
The grub boot menu can be edited via:
Sudo gedit /boot/grub/menu.lst
The lines you're looking for are similar to:
## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash noapic nolapic
After editing this, hit save, and in terminal type:
Sudo update-grub
After a restart, you should be in business.
For me, this worked perfectly and now I am enjoying the speed boost of hyper-threading.
Now I know the above would seem obvious to some, but to me (a noob) it wasn't. So as you want users to help other users, I thought I would put this short How To together. Moderators, feel free to move it to where ever it should go if it doesn't belong in this category.
Lylepalooza