How to get number of physical CPUs in RHEL & SuSE

[sathya_nars]

From my application code, I want to get number of physical processors present in system (RHEL & SuSE). How do i go about?

sysconf( ) - provides only logical CPUs count, not physical CPUs count

[lee_harris]

Hi,

Not sure about SuSE, but in RedHat EL you can use the physical id parameter found in /proc/cpuinfo. This will actually give you physical cores as opposed to sockets.

Single CPU Xeon system with H/T (2 logical) would show as 1.
Dual CPU AMD Opteron (4 physical cores, 2 sockets) would show as 4.

grep "^physical is" /proc/cpuinfo | awk '{print $NF}' | uniq | wc -l

Hope that helps - Lee

[vwvr9]

cat /proc/cpuinfo | egrep "processor|physical\ id|core\ id|cpu\ cores"

Look at the "physical\ id" for physical CPU count and "cpu\ cores" for the core count

[root@abibi ~]# cat /proc/cpuinfo | egrep "processor|physical\ id|core\ id|cpu\ cores"
processor       : 0
physical id     : 0
core id         : 0
cpu cores       : 4
processor       : 1
physical id     : 0
core id         : 1
cpu cores       : 4
processor       : 2
physical id     : 0
core id         : 2
cpu cores       : 4
processor       : 3
physical id     : 0
core id         : 3
cpu cores       : 4
processor       : 4
physical id     : 1
core id         : 0
cpu cores       : 4
processor       : 5
physical id     : 1
core id         : 1
cpu cores       : 4
processor       : 6
physical id     : 1
core id         : 2
cpu cores       : 4
processor       : 7
physical id     : 1
core id         : 3
cpu cores       : 4
[root@abibi ~]#