From: "John Anthony Kazos Jr." <jakj@j-a-k-j.com>
Subject: Re: Ext3 behavior on power failure
Date: Wed, 28 Mar 2007 09:17:27 -0400 (EDT)
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Cc: Ric Wheeler <ric@emc.com>, armangau_philippe@emc.com,
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To: Jan Kara <jack@suse.cz>
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>  If you fsync() your data, you are guaranteed that also your data are
> safely on disk when fsync returns. So what is the question here?

Pardon a newbie's intrusion, but I do know this isn't true. There is a 
window of possible loss because of the multitude of layers of caching, 
especially within the drive itself. Unless there is a super_duper_fsync() 
that is able to actually poll the hardware and get a confirmation that the 
internal buffers are purged?