topic "switching off" one or more CPUs on a multi-CPU machine in Operating System - HP-UX

"switching off" one or more CPUs on a multi-CPU machine

Robert Taylor_1 — Fri, 08 Feb 2002 06:05:11 GMT

Hi!

I have a 6-CPU N-class machine running HPUX 11.0.

Is it possible for me to "idle" or "switch-out" one or more of the CPUs and gradually bring them back on line during some performance testing?

Re: "switching off" one or more CPUs on a multi-CPU machine

Amruth — Fri, 08 Feb 2002 06:36:10 GMT

Hi Robert,

It is possible. This should be done before machine boots. In the ISL prompt go to Configuration or Serive menu you will get the option for enabling/disabling the Cpus.

Good luck.
AR

Re: "switching off" one or more CPUs on a multi-CPU machine

Trond Haugen — Fri, 08 Feb 2002 06:43:03 GMT

I belive that with the iCOD SW you can do that. It should be downloadable from software.hp.com. You will have to reboot to disable CPUs. But can enable on the fly.

Trond

Re: "switching off" one or more CPUs on a multi-CPU machine

Ravi_8 — Fri, 08 Feb 2002 10:27:11 GMT

Hi,
From the main menu(by pressing any key within 10 secs while booting)
main menu> config
main menu> proconfig x off
main menu> reset

here x is the processor number that you wanted to make inactive

Re: "switching off" one or more CPUs on a multi-CPU machine

Xavier Gutierrez — Fri, 08 Feb 2002 16:25:20 GMT

Hi, Robert.

It can be performed online with the Support Tools Manager (STM) but you need a support only license:

**************************

-- Expert Tool Information Log for CPU on path 32 --

Version A.01.03

This program may only be used by HP support personnel and those customers with the appropriate Class license for systems specified by the license. HP shall not be liable for any damages resulting from misuse or unauthorized use of this program. This program remains the property of HP.

The CPU Expert Tool provides the user with the ability to enable or disable individual processor modules without requiring reset of the SPU or restart of the operating system in a multiprocessor environment. Problems caused by a CPU module or specific process can be identified without offline testing.
Deallocation of a CPU module(s) in single-processor system or deallocation of all processors will not be allowed. The Monarch Processor will always stay allocated during execution of the CPU Expert Tool.

NOTE: I/O redirection is not enabled at this time. this means that deallocation of a processor will only prevent HP-UX from dispatching processes on this processor. I/O will continue to take place using this processor until HP_UX implements I/O redirection.

(C) Copyright Hewlett Packard Co.
1997, 1999, 2000
All Rights Reserved

************************************

This is taken from STM. Just select one of your CPUs and go to Tools, Expert Tool, Info.

Be careful when trying iCOD, because you may be charged for it. You also need to get a license from HP...

I think it's better to agree a visit of HP Support Personnel for the tests and ask them to switch off the CPUs for you...

Best regards,

Xavier.