I'm running Ubuntu 14.04 on an Intel Core i7-2620m , (2.7 Ghz). I've checked in the bios that hyperthreading is activated, but on when doing less /proc/cpuinfo, hyperthreading appears off (sibling count = cpu count). Is there any specific configuration step i need to make in Ubuntu?
/proc/cpuinfo shows 4 cpus with id 0 to 3, and sibling 4
The Intel® Core™ i7-2620M has two physical and four virtual cores.
/proc/cpuinfo shows each virtual core as a separate processor. If you're seeing four of them, hyperthreading is working as intended.