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From: Matthew Garrett <mjg59@srcf.ucam.org>
To: hagar <hagar@iinet.net.au>
Cc: lkml <linux-kernel@vger.kernel.org>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Srivatsa Vaddagiri <vatsa@in.ibm.com>,
	Joel Schopp <jschopp@austin.ibm.com>,
	Ashok Raj <ashok.raj@intel.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>
Subject: Re: Fwd: Kernel Power management ?? turning off used devices that are in use.
Date: Mon, 7 Nov 2011 17:04:58 +0000	[thread overview]
Message-ID: <20111107170458.GA23257@srcf.ucam.org> (raw)
In-Reply-To: <4EB38C99.10809@iinet.net.au>

On Fri, Nov 04, 2011 at 02:56:25PM +0800, hagar wrote:
> 
> I have traced this behaviour to the cpu hotplug code.
> 
> I need to be able to either switch off cpu hotpluging - or at least
> prevent hotplugging certain cpu's

The kernel doesn't automatically hotplug CPUs on idle. Something in your 
userspace is doing so. I think that Ubuntu's powernap will do so under 
certain circumstances - try disabling that if you have it.

(Which doesn't alter the fact that there appears to be a bug here)

-- 
Matthew Garrett | mjg59@srcf.ucam.org

  reply	other threads:[~2011-11-07 17:05 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-25  8:37 Kernel Power management ?? turning off used devices that are in use hagar
     [not found] ` <4EB38A44.5030606@iinet.net.au>
2011-11-04  6:56   ` Fwd: " hagar
2011-11-07 17:04     ` Matthew Garrett [this message]
2011-11-04 15:24   ` Joel Schopp
2011-11-05  0:07     ` hagar

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