LINUX - Determine number of CPU cores

# cat /proc/cpuinfo | egrep “physical\ id|core\ id”

physical id : 0
core id : 1
cpu cores : 2

If you have two CPUs in cpuinfo with the same physical id and core id, than – hyperthreading! When you have all CPUs with different physical ids, than you have SMP, and when you have CPUs with one physical id and different core ids – you have one multicore CPU. And so on…