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From: Robert Watson <rwatson@FreeBSD.org>
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Cc: Frank Behrens <frank@ilse.behrens.de>, Jeff Roberson <jeff@FreeBSD.org>,
	"current@freebsd.org" <current@FreeBSD.org>, stable@FreeBSD.org
Subject: Re: The machdep.hyperthreading_allowed & ULE weirdness in 7.1
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On Mon, 23 Feb 2009, Robert Watson wrote:

> It's not quite that simple -- in a world of device drivers pinning threads to 
> CPUs for workload distribution, callout threads and sched_bind()/sched_pin() 
> for crypto load distribution, etc, you need a whole infrastructure for 
> software-disabled CPUs.  Disabling it using the BIOS or device.hints is the 
> only reliable way to do this right now.  Changing the architecture of the 
> kernel to disable CPU cores after boot is a significant investment of work,

             ^^^^ s/disable/desirable/

Robert N M Watson
Computer Laboratory
University of Cambridge