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To: Ian Lepore <ian@FreeBSD.org>
Subject: Re: access to hard drives is "blocked" by writes to a flash drive
In-reply-to: <1362318887.1195.221.camel@revolution.hippie.lan>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Sun, 03 Mar 2013 14:10:40 +0000
Message-ID: <52961.1362319840@critter.freebsd.dk>
Cc: deeptech71 <deeptech71@gmail.com>, freebsd-current@FreeBSD.org,
 Peter Jeremy <peter@rulingia.com>
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In message <1362318887.1195.221.camel@revolution.hippie.lan>, Ian Lepore writes
:

>Hmmm, so the problem has been known and unfixed for 10 years.

It's hard to fix, because a lot of stuff has been tangled up
cyclically in the disk-I/O relevant layers.  The "umapped buf"
stuff which is (finally!) happening, is the path to fixing it.

-- 
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.