From owner-freebsd-fs  Wed Mar 13  9: 7:37 2002
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Date: Wed, 13 Mar 2002 09:07:28 -0800
From: Alfred Perlstein <bright@mu.org>
To: Parity Error <bootup@mail.ru>
Cc: freebsd-fs@FreeBSD.org
Subject: Re: metadata update durability ordering/soft updates
Message-ID: <20020313170728.GM32410@elvis.mu.org>
References: <E16l7YD-0001FG-00@f9.mail.ru>
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* Parity Error <bootup@mail.ru> [020313 04:08] wrote:
> with soft-updates metadata updates are delayed write. I am wondering if, say
> there 
> are two independent structural changes, one after another, and then a crash
> happens. 
> Is there a possibility that the latter structural change got written to disk
> before the 
> former due to some memory replacement policy ?
> 
> could this affect the correctness of some applications ?

Of course!  This happens with almost any filesystem.

This is why you have fsync(2).

-Alfred

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