Comments on: Howto display the number of processors in Linux

By: Tracy Phillips

Tracy Phillips — Sun, 03 May 2009 19:52:12 +0000

You can run the command below and you will see number of physical processors in the server:

[server][root][~]# grep "^physical is" /proc/cpuinfo | awk '{print $NF}' | uniq | wc -l
1

Now lets determine how many cores we have:

[server][root][~]# cat /proc/cpuinfo  | grep processor | wc -l
4

So from the above, we are able to determine that we have a single CPU quad core chip.

By: cbn

cbn — Thu, 08 Jan 2009 22:08:01 +0000

you say: how to display the _number_
$ grep -c processor /proc/cpuinfo
2

By: Randall

Randall — Wed, 19 Sep 2007 20:28:12 +0000

If your kernel does not have SMP support compiled in, `cat /proc/cpuinfo` will only show one processor, even if you have more than one cpu.

By: Bubax

Bubax — Mon, 03 Sep 2007 07:52:43 +0000

Your script is broken:

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Thank you. Your comment has been approved.

By: Bubax

Bubax — Mon, 03 Sep 2007 07:50:11 +0000

> Simply issue the following command as root

*Not* as root, because:
# ls -l /proc/cpuinfo
-r–r–r– 1 root root 0 2007-09-03 15:49 /proc/cpuinfo

(Unless your system uses other permissions than mine, but I don’t see why it should do that.)

Misuse of cat:
> # cat /proc/cpuinfo | grep processor

Simply use:
# grep processor /proc/cpuinfo

By: Igor

Igor — Mon, 03 Sep 2007 01:45:19 +0000

There is a lot simpler solution. Just type ‘top’ at the command prompt and then press ‘1′ (number one).
You will see the ACTUAL CPUs listed on the top of the page

By: Eddie303

Eddie303 — Sun, 02 Sep 2007 10:48:29 +0000

Lev: I once ate that with some proliant server, it had only one CPU, and because of HyperThreading, I thought there are 2…

By: Lev

Lev — Fri, 24 Aug 2007 13:10:15 +0000

Ever heard of hyperthreading? If it’s on in the BIOS, it’ll incorrectly double the number…