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To: Nate Lawson <nate@root.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 18 Oct 2003 13:02:29 PDT."
             <20031018130119.T47207@root.org> 
Date: Sat, 18 Oct 2003 22:05:40 +0200
Message-ID: <9670.1066507540@critter.freebsd.dk>
cc: arch@freebsd.org
Subject: Re: Variable timer tick rate? 
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In message <20031018130119.T47207@root.org>, Nate Lawson writes:

>This is an interesting approach.  If there are no upcoming timeouts,
>decrease the tick rate.  Of course, you have to amortize the cost of
>resetting the timer over the period of no ticks.
>
>http://kerneltrap.org/node/view/1006

Yes, unfortunately we may have a couple of timeout() (ab)users which
use it to implement "as fast as possible polling" by calling timeout
with a 1 tick argument, so last I looked (a couple of years ago)
it fired every tick.

-- 
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.