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To: Bruce Evans <bde@zeta.org.au>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 15 Oct 2005 09:20:26 +1000."
	<20051015084425.C1403@epsplex.bde.org> 
Date: Sat, 15 Oct 2005 07:12:51 +0200
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Cc: Garrett Wollman <wollman@csail.mit.edu>,
	Andrew Gallatin <gallatin@cs.duke.edu>, net@freebsd.org
Subject: Re: Call for performance evaluation: net.isr.direct (fwd) 
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In message <20051015084425.C1403@epsplex.bde.org>, Bruce Evans writes:
>On Fri, 14 Oct 2005, Poul-Henning Kamp wrote:

>> Even to this day new CPU chips come out where TSC has flaws that
>> prevent it from being used as timecounter, and we do not have (NDA)
>> access to the data that would allow us to build a list of safe
>> hardware.
>
>Um, I have already pointed out that NDAs are not necessary.
>
>They (and staic lists) are also not sufficient.  [...]

Which is why I am totally set against using the TSC on SMP machines
and only grudingly accept it for UP machines that do not have
ACPI counters.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.