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Date: Fri, 16 Dec 2011 13:39:01 -0800
From: Doug Barton <dougb@FreeBSD.org>
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Cc: Tom Evans <tevans.uk@googlemail.com>, "C. P. Ghost" <cpghost@cordula.ws>,
	Luigi Rizzo <rizzo@iet.unipi.it>,
	Jeremy Chadwick <freebsd@jdc.parodius.com>, freebsd-stable@freebsd.org
Subject: Re: switching schedulers (Re: SCHED_ULE should not be the default)
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On 12/16/2011 12:53, Adrian Chadd wrote:
> Hi all,
> 
> Can someone load a kernel module dynamically at boot-time?
> 
> Ie, instead of compiling it in, can 4bsd/ule be loaded as a KLD at
> boot-time, so the user can just change by rebooting?
> 
> That may be an acceptable solution for now.

That, or a loader.conf tunable (which in the case of making them modules
would basically amount to the same thing, right?).

I've heard several really smart people with rather convincing
explanations of why ULE is not the right choice for default for 2 cores
or less. If we could ship one kernel with both schedulers available it
should be simple to modify the installer to choose the right one and put
the right stuff in loader.conf.


Doug

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