On a MacBookPro 7,1 running ubuntu 11.10, System monitor only sees 1 core (instead of 2).
cat /proc/cpuinfo | grep 'cpu cores'
cpu cores : 1
I followed this guide and added
acpi_apic_instance=2 to the line with
GRUB_CMDLINE_LINUX_DEFAULT, but that doesn't seem to change the situation.
What can I do? I'm using rEFIt, installed under MacOS, and running in dual boot with MacOS. After the rEFIT menu, I'm still presented with the GRUB menu (I'm assuming that's normal).
I saw similar posts on this matter, but could not fix my problem with what they suggested.
EDIT: With the method mentioned above the computer runs sometimes with 1 core and other times with 2. Why is that? How can it be fixed?