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To: Scott Long <scottl@samsco.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 06 Sep 2005 11:16:43 MDT."
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Date: Tue, 06 Sep 2005 19:50:21 +0200
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Cc: src-committers@FreeBSD.org, Luigi Rizzo <rizzo@icir.org>,
	Nate Lawson <nate@root.org>, cvs-all@FreeBSD.org,
	Gleb Smirnoff <glebius@FreeBSD.org>,
	Robert Watson <rwatson@FreeBSD.org>, cvs-src@FreeBSD.org
Subject: Re: cvs commit: src/sys/kern kern_poll.c 
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In message <431DCEFB.9030005@samsco.org>, Scott Long writes:

>> For the case of storage, you actually have a better model since all 
>> transactions are initiated from the host (as opposed to packet 
>> arrivals).  This gives an easy metric for a dynamic polling threshold -- 
>> if you have a deep queue of outstanding requests and one completes, you 
>> should poll a little more than normal.
>
>Except for target mode.

It could be argued that target mode is really networking rather
than storage :-)

-- 
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.