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From: Warner Losh <imp@bsdimp.com>
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To: Adrian Chadd <adrian@FreeBSD.org>
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Cc: Oleksandr Tymoshenko <gonzo@FreeBSD.org>,
	"freebsd-embedded@freebsd.org" <freebsd-embedded@FreeBSD.org>
Subject: Re: Updated switch/glue patch?
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On Dec 18, 2011, at 9:20 PM, Adrian Chadd wrote:

> On 18 December 2011 16:29, Warner Losh <imp@bsdimp.com> wrote:
>=20
>> What is it without WITNESS?  The performance numbers with WITNESS are =
generally uninteresting for a deployed system.
>=20
> It's still ridiculously CPU intensive. :( It turns out trying to do
> those locks three times one each GPIO IO line fiddle is a bit over the
> top.

That's the real problem.  WITNESS is a known pigdog on low-end systems, =
so measurements with it tend to skew the results a tad too much.  On the =
other hand, it did magnify the problem to the point it was fixed :)

The insane locking should be fixed.

Warner