How to Enable 4 Extra CPU

[Shreenath]

Ohh,
I need only 4CPU enabled. Then how to disable remaining 4 CPU.

# ioscan -kfC processor
Class I H/W Path Driver S/W State H/W Type Description
===================================================================
processor 0 120 processor CLAIMED PROCESSOR Processor
processor 1 121 processor CLAIMED PROCESSOR Processor
processor 2 122 processor CLAIMED PROCESSOR Processor
processor 3 123 processor CLAIMED PROCESSOR Processor
processor 4 124 processor CLAIMED PROCESSOR Processor
processor 5 125 processor CLAIMED PROCESSOR Processor
processor 6 126 processor CLAIMED PROCESSOR Processor
processor 7 127 processor CLAIMED PROCESSOR Processor

Thanks,

Regards,
Shreenath

[Torsten.]

stop at efi shell and use "cpuconfig" to disable cpu modules.

[Shreenath]

Hi Torsten,
EFI Shell ???? Do i need to ask this to IT team or I can do it remotely ( If i am having root password)
Can you please tell something more about how to use EFI shell
Thanks a lot your quick responce.

Regards,
Shreenath

[Torsten.]

You can access EFI shell remotely if you have access to the MP.

Why you want to disable the CPUs?

[rick jones]

EFI shell - think BIOS with a niftier interface :) the cpuconfig command there can be used to enable/disable entire processors (both cores at once) and/or enable/disable hyperthreading.

Getting to the EFI shell requires rebooting, and then, while at the console interrupting the boot at the EFI boot menu and selecting EFI. I suspect that there are one or more manuals on docs.hp.com that discuss EFI and/or the cpuconfig command therein so those are good search input fodder.

Depending on the specific nature of what you want to do, you might also consider shoving CPUs into psets, not assign any processes to the pset(s) and then making sure those psets don't take interrupts (man intctl). That would be one way you could essentially disable CPUs on a live system. HP-UX 11.31 also has the ability to enable/disable use of hyperthreads on a pset by pset basis...

So, *specifically* what do you want to do that has you wanting to disable CPUs?

[Shreenath]

Hi,
i am testing performance of the product on
2,4,8 CPU machine. Instad of having different machine for 2,4,8 CPU i thought of having one machine and use that by enable/disable the cpu
Regards,
Shreenath

[rick jones]

2, 4 and 8 CPU - since this is on a four socket system with dual-core processors I presume you mean 1, 2 and 4 sockets/processors for 2 4 and 8 active cores. I would suggest the aforementioned EFI path and the cpuconfig command. It involves rebooting, but it will be easier IMO.

As you go, you may want to make use of the features of Caliper:

http://www.hp.com/go/caliper