Visit The New, Modern Unix Linux Community

CPU Count

Thread Tools Search this Thread
Operating Systems Linux Red Hat CPU Count
# 1  
CPU Count


I am observing high load average on RHEL5 server and need to check the number of core processors available on the box to give me a bigger picture on whether or not I should be worried.

I have always checked the physical count quite simply.....

# grep 'physical id' /proc/cpuinfo | sort | uniq | wc -l

....however can anyone confirm that the below output truely represents the actual number of core processors available on my server?

# cat /proc/cpuinfo | grep processor | awk '{a++} END {print a}'

# 2  
You get a useless use of cat award. And if you're using awk, why bother using grep?

I'd grep for something a little less generic than 'processor'. That might turn up in a CPU name or something potentially. And pin it to the beginning of the line where it should always be found.

 awk '/^cpu MHz/ { a++ } END { print a }' /proc/cpuinfo

# 3  
I am aware of that so (without printing the entire cpuinfo) "processor : 7" equates to 8 core CPU's? - Just looking for a consensus/confirmation.
# 4  
It could mean one 8-core CPU, a pair of 4-core CPU's, four 2-core CPU's, or 8 1-core CPU's. Cores are counted individually. If you care which belongs in what chip, that's the physical ID.

If you just care about the number of cores, counting the line match like that will work fine.

In fact, you don't need to even match anything. Just count the number of records, splitting on blank lines, by setting RS to "". Then when awk runs out of input, print NR, the number of records. On my dual-core system:

$ awk -v RS="" 'END { print NR }' /proc/cpuinfo

# 5  
Yip, simply looking for the number of cores which according to this is 8. Thing is though it does not correspond to what the hardware mgmt interface sayes?

# hpasmcli
HP management CLI for Linux (v2.0)
Copyright 2008 Hewlett-Packard Development Group, L.P.
hpasmcli> show server
System : ProLiant BL460c G6
Serial No. : GB8033X7FV
ROM version : I24 03/30/2010
iLo present : Yes
Embedded NICs : 2
NIC1 MAC: 78:e7:d1:65:3a:60
NIC2 MAC: 78:e7:d1:65:3a:64
Processor: 0
Name : Intel Xeon
Stepping : 5
Speed : 2933 MHz
Bus : 133 MHz
Core : 4
Thread : 8
Socket : 1
Level2 Cache : 1024 KBytes
Status : Ok
Processor total : 1

# 6  
If you'd bothered posting your /proc/cpuinfo, I might be able to explain, but at present I can only guess.

Do your CPU's have hyperthreading? That will show up as double the number of cores in Linux.
# 7  
Ok, cpuinfo attached...

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #970
Difficulty: Medium
The Android operating system includes the Linux kernel.
True or False?

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Why Entitlement CPU can't be set to same as Virtual CPU?

I read that Entitlement CPU should be set to max 75% compare to Virtual CPU. May I know the reason. I have set the Entitlement CPU = Virtual CPU on AIX . It works fine . Can you help to understand. (1 Reply)
Discussion started by: gabhanes
1 Replies

2. AIX

Topas - CPU count inconsistent across LPARs

seeing weirdness across some LPARs - they all have 2 vCPUs allocated shared. With prtconf they show 2 CPUs, 'lsdev -c processor' concurs, and 'lsattr -El procX' shows that SMT is enabled and there are 2 SMT threads (power5, sorry). Yet running topas on them shows 2 CPUs on some and 4 on... (3 Replies)
Discussion started by: maraixadm
3 Replies

3. UNIX for Dummies Questions & Answers

Is it possible to combine multiple CPU to act as a single CPU on the same server?

We have a single threaded application which is restricted by CPU usage even though there are multiple CPUs on the server, hence leading to significant performance issues. Is it possible to merge / combine multiple CPUs at OS level so it appear as a single CPU for the application? (6 Replies)
Discussion started by: Dissa
6 Replies

4. Red Hat

finding CPU count - reading sysinfo output

Hello, sysinfo throws out below 3 CPU counts. Can anyone help me understand what each of these means? CPU Count Socketed is 2 CPU Count Physical is 8 CPU Count Virtual is 16 First one seems obvious. However, I wonder how there can be 8 Physical CPUs, if... (2 Replies)
Discussion started by: hnhegde
2 Replies

5. AIX

topas and mpstat disagree on CPU count

I have a number of LPARs on one P520. All LPARs are running 5.3 and I observe the following: On some LPARs the number of CPUs found do not match between topas and mpstat. Server 1: $ mpstat System configuration: lcpu=4 ent=0.2 mode=Uncapped cpu min maj mpc int cs ics rq ... (1 Reply)
Discussion started by: petervg
1 Replies

6. UNIX for Dummies Questions & Answers

virtualization (VCPU count according to CPU)

We have purchased four intels xeon processors Intel® Xeon® Processor E7530 (12M Cache, 1.86 GHz, 5.86 GT/s Intel® QPI) with SPEC Code(s) SLBRJ As per the specification each cpu has 6 cores therefore we have 24 cores (considering 4 cpus). Now how would i calculate the number of vcpus that can... (1 Reply)
Discussion started by: pinga123
1 Replies

7. Solaris

cpu-shares vs cpu-cap in solaris

Can anyone tell me difference between cpu-shares vs cpu-cap in solaris & how FSS will work with cpu-caps ? (9 Replies)
Discussion started by: fugitive
9 Replies

8. Solaris

Multi CPU Solaris system shows 100% CPU usage.

Hello Friends, On one of my Solaris 10 box, CPU usage shows 100% using "sar", "vmstat". However, it has 4 CPUs and prstat and glance are not showing enough processes to justify high CPU utilization. ========================================================================= $ prstat -a ... (4 Replies)
Discussion started by: mahive
4 Replies

9. UNIX for Dummies Questions & Answers

how to get persistant cpu utilization values per process per cpu in linux (! top,ps)

hi, i want to know cpu utilizatiion per process per cpu..for single processor also if multicore in linux use these values in shell script to kill processes exceeding cpu (pcpu) command does not give exact does not give persistant values..psstat,vmstat..does njot... (3 Replies)
Discussion started by: pankajd
3 Replies

10. UNIX for Dummies Questions & Answers

CPU count

Is there an easy way in Solaris to count the number of processors? (2 Replies)
Discussion started by: hshapiro
2 Replies

Featured Tech Videos