topic Re: disable CPU using icod in Operating System - HP-UX

disable CPU using icod

skt_skt — Tue, 12 Aug 2008 13:20:39 GMT

i wanted to disable a CPU which is online and currently serving the imterrupts.So that all future interrupts would be served by another CPU. I have added the CPU online (icapmodify -a 8). But never dsisabled online.So that all future interrupts would be served by another CPU.

is that possible online? what tool we need for that?

HP-UX 11.11
PA RISC

is there separate tool if 11.23?

Re: disable CPU using icod

Duncan Edmonstone — Tue, 12 Aug 2008 14:22:26 GMT

Santhosh,

I'm not sure why you are worrying about interrupts - iCAP will take care of all that behind the scenes - removing those CPUs is done exactly the same as adding them:

icapmodify -d 8

would remove 8 CPUs from the partition the command was run in.

If you really want to look at what's happening with interrupts then install this software on 11.11:

http://h20392.www2.hp.com/portal/swdepot/displayProductInfo.do?productNumber=INTRMIGR

This provides you with the intctl command which allows you to move CPU interrupts around. In some extreme situations if you are really trying to squeeeze every ounce of performance out of a system, moving an interrupt to a CPU which is cell-local to the IO card the interrupt is serving might offer some advantage, but I really wouldn't sweat this stuff unless your're into serious benchmarking.

If I recall correctly, intctl is part of the OS on 11.23 and 11.31.

HTH

Duncan

Re: disable CPU using icod

skt_skt — Tue, 12 Aug 2008 15:43:31 GMT

is that possible to disable a single/specic CPU?

Re: disable CPU using icod

Tim Nelson — Tue, 12 Aug 2008 16:14:58 GMT

As a last resort you can always disable specific CPUs using MP commands.

But this requires an outage.

Re: disable CPU using icod

Court Campbell — Tue, 12 Aug 2008 16:32:54 GMT

yes, icapmodify -d 1.