topic Re: sizing npty (kernel variable) in Operating System - HP-UX

sizing npty (kernel variable)

Nabil Boussetta — Thu, 09 Jun 2005 03:27:04 GMT

i'have an rp7410 machine ( 1cell, 4 procs, 16GB of memory) running HP-UX11i v1.
many users(between 500 and 1000 user) connect to the system.

the default value of npty is 60. i should increase this value to 1000. is it possible whithout any impact on the system ?

Re: sizing npty (kernel variable)

Muthukumar_5 — Thu, 09 Jun 2005 03:34:27 GMT

npty parameter information is as,

Parameter: npty
Current: 60
Planned: 60
Default: 60
Minimum: -
Module: -
Version: -
Dynamic: No

It is not a dynamic one so kernel rebuild and rebooting needed.

hth.

Re: sizing npty (kernel variable)

Eknath — Thu, 09 Jun 2005 04:03:09 GMT

Hi,

You can increase npty value. Bur since its dynamic a system reboot is required. So plan an outage before modifying this.

pls visit
http://docs.hp.com/en/B3921-90010/npty.5.html for more information.

Cheers!!!
eknath

Re: sizing npty (kernel variable)

Devender Khatana — Thu, 09 Jun 2005 04:07:37 GMT

Hi,

It can be increased and do not affect anything.

Eknath - It is not dynamic that is why reboot is required.

HTH,
Devender

Re: sizing npty (kernel variable)

Cem Tugrul — Thu, 09 Jun 2005 08:08:52 GMT

from my syytem;
baan01:/#kmtune -q npty -l
Parameter: npty
Current: 300
Planned: 300
Default: 60
Minimum: -
Module: -
Version: -
Dynamic: No
baan01:/#uname -a
HP-UX baan01 B.11.11 U 9000/800 1020982799 unlimited-user license

"Static" kernel parameters need new kernel
build so require reboot...

Good Luck,

Re: sizing npty (kernel variable)

Patrick Wallek — Thu, 09 Jun 2005 08:17:16 GMT

How are the users connecting to the system?

If they are connecting via telnet or SSH then I would increase npty, nstrpty and nstrtel.

If users are connecting via SQLNET or some other means of database connectivity then you don't need to do anything.

Re: sizing npty (kernel variable)

Jeff Schussele — Thu, 09 Jun 2005 08:18:26 GMT

Hi Nabil,

I would increase beyond the possible max value by at least 10% & probably 20%.
Remember that when you increase npty you should also increase nstrpty & nstrtel to the same values as well.

HTH,
Jeff

Re: sizing npty (kernel variable)

Steven E. Protter — Thu, 09 Jun 2005 08:22:37 GMT

You need to size it based on use.

On a thousand user machine 60 won't cut it unless nobody is using it or everyone is really and oracle client or something.

Set it high and monitor it. because multiple sessions are possible in some applications, I'd set for 1200.

SEP