How to get number of main CPU/Core using Bash? (Solved)

[LazY Puppy]

Hi.

I need to find out how many main CPU/Core are on the mother board.

How can I do this in bash?

Thanks.

[unicorn316386]

I did this and got 1 (might try '..$' if more than 9)

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grep -r "cpu cores" /proc/cpuinfo | grep -o '.$'

[rufwoof]

Hmm! Puppy pc single core on desktop 1, rdp'd into another puppy with 4 cores on desktop 2, and rdp'd into a windows box with 4 cores on desktop 3, and rdp'd into a android on desktop 4 = TEN

But /proc/cpuinfo is only showing ONE ???

[LazY Puppy]

Ok.

Terminal Output:

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root# CORES=`grep -r "cpu cores" /proc/cpuinfo | grep -o '.$'`; echo $CORES
2 2
root#

Prozessor is: Intel(R) Core(TM)2 Duo CPU E6750 @ 2.66GHz

File /proc/cpuinfo shows processor 0 and processor 1

Processor 0 cpu cores shows 2
Processor 1 cpu cores shows 2 also

So this means the mother board has 2 CPU and each CPU has 2 cores?

So there are 4 cores, no?

[unicorn316386]

@LazY Puppy: Your E6750 has 2 cores in total, but looks like lscpu can break it down better

Actual Cores:

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lscpu | grep -i "Core(s)" | grep -o ".$"

Threads / Virtual Cores (should double only if there's hyper-threading):

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lscpu | grep -i "CPU(s):" | grep -o ".$"

The top result seems to match with the Intel definition of a core/CPU from what I can tell
http://ark.intel.com/products/30784/Intel-Core2-Duo-Processor-E6750-4M-Cache-2_66-GHz-1333-MHz-FSB

Cores is a hardware term that describes the number of independent central processing units in a single computing component (die or chip).

@rufwoof: I guess each puppy has it's own /proc/cpuinfo ? Never tried rdp so your guess is probably better than mine

[LazY Puppy]

Thanks to everyone for the replies.

Marked as solved.

[amigo]

cpuinfo only reflects the *capacity* of the cpu, without telling you how many cores are actually being used. This:

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$ ls /sys/devices/system/cpu/
cpu0  cpufreq  kernel_max  offline  possible  present  release
cpu1  cpuidle  modalias    online   power     probe    uevent
$ cat /sys/devices/system/cpu/kernel_max 
255
$ cat /sys/devices/system/cpu/offline 
2-63
$ cat /sys/devices/system/cpu/possible 
0-63
$ cat /sys/devices/system/cpu/present 
0-1
$ cat /sys/devices/system/cpu/online 
0-1

The last two commands are the most telling.

[Karl Godt]

cpu frequency scaling is another way to check if the CPU is a Core or a Thread .

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# file /sys/devices/system/cpu/cpu[0-9]/cpufreq

/sys/devices/system/cpu/cpu0/cpufreq: directory
/sys/devices/system/cpu/cpu1/cpufreq: directory
/sys/devices/system/cpu/cpu2/cpufreq: symbolic link to `../cpu0/cpufreq'
/sys/devices/system/cpu/cpu3/cpufreq: symbolic link to `../cpu1/cpufreq'

The links are for threads, directories are for cores ( I think kernel 2.6.37.4-KRG-p4_1 ) .