How to determine the number of processors?

[Harri Pasanen]

How can I determine the number of processors a machine has?

CPU count is useful info when implementing optimal threading algorithms.

On Solaris it the info is available through sysconf(), but apparently not on HP-UX 11.00.

[Alex Glennie]

top should tell you however to do this programatically the followinh should work ?

#include
main () {
struct pst_dynamic psd;
pstat_getdynamic(&psd, sizeof(struct pst_dynamic), 1, 0);
printf("Number of Active Processors: %d\n", psd.psd_proc_cnt);
}

[Alex Glennie]

This works too on my 11.xx & 10.20 systems :

echo "processor_count/D" | adb -k /stand/vmunix /dev/mem

[Frederic Soriano]

Hello Harri,

Besides the programmatical way, there is another possibility, via the command line; as root, issue the following command:

echo 'processor_count/D' | adb -k /stand/vmunix /dev/kmem | tail -1 | awk '{print $2}'

Regards.

[federico_3]

you could use:

#ioscan -fnkCprocessor | grep processor | wc -l

Also the top command could help you. type:
#top

and you will see the Cpu states with their number



Federico

[CHRIS_ANORUO]

You can also get the number with the following line command:
cat /var/adm/syslog/syslog.log|grep processor
or
cat /var/adm/syslog/syslog.log|grep processor|wc -l
or
dmesg|pg

[Alan Riggs]

Just for fun:

sar -M 1 1| tail +6|wc -l

[CHRIS_ANORUO]

To add to my previous contribution:
vi /var/tombstones/ts99 and look for the PA's. You will also see the firmware and others under the Revision table.

[Jiri D]

Hi Harri

You can try this command:
ioscan -k | grep proc

Jiri

[Harri Pasanen]

Thanks for the answers.
I wanted to do this programmatically, so the C code answer was what I was looking for. Should have given it 10 points, 6 was by accident.

Interactive answers were also useful, so I gave some points for those, more to those were you don't have to be root.
Some suggestions gave bogus answers, like 32 processors, (I wish).