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To: Luigi Rizzo <rizzo@icir.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 26 Jul 2005 06:54:44 PDT."
	<20050726065444.A37735@xorpc.icir.org> 
Date: Tue, 26 Jul 2005 15:56:58 +0200
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Cc: s223560@studenti.ing.unipi.it, current@freebsd.org
Subject: Re: multiple pending filesystem requests for the same block ? 
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In message <20050726065444.A37735@xorpc.icir.org>, Luigi Rizzo writes:
>(context: SoC work on pluggable disk schedulers,
>	http://wikitest.freebsd.org/moin.cgi/Hybrid
>
>
>The doubt we have is the following:
>
>	can the filesystem code have multiple pending write requests for
>	the same disk block ?

If the filesystem does that, it will get no guarantee in which order
they are written.

-- 
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.