From: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
To: Jeff Garzik <jgarzik@pobox.com>, "Stephen C. Tweedie" <sct@redhat.com>
Subject: Re: [PATCH] barrier patch set
Date: Wed, 31 Mar 2004 00:40:43 +0200
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On Wednesday 31 of March 2004 00:21, Jeff Garzik wrote:
> Stephen C. Tweedie wrote:
> > Yep.  It scares me to think what performance characteristics we'll start
> > seeing once that gets used everywhere it's needed, though.  If every raw
> > or O_DIRECT write needs a flush after it, databases are going to become
> > very sensitive to flush performance.  I guess disabling the flushing and
> > using disks which tell the truth about data hitting the platter is the
> > sane answer there.
>
> For IDE, O_DIRECT and O_SYNC can use special "FUA" commands, which don't
> return until the data is on the platter.

Do you know of any drive supporting it?  I don't.

Bartlomiej

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