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	for linux-mtd@lists.infradead.org; Mon, 08 Jun 2009 05:50:31 +0000
Subject: Re: about ubifs
From: Artem Bityutskiy <dedekind@infradead.org>
To: Jamie Lokier <jamie@shareable.org>
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Date: Mon, 08 Jun 2009 08:49:55 +0300
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Cc: linux-mtd@lists.infradead.org, tommy <jiujin.hong@mid-fun.com>,
	Corentin Chary <corentin.chary@gmail.com>
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On Mon, 2009-06-08 at 02:35 +0100, Jamie Lokier wrote:
> Corentin Chary wrote:
> > On Fri, Jun 5, 2009 at 3:03 PM, tommy<jiujin.hong@mid-fun.com> wrote:
> > > no,i didn't fsync when i close file !
> > >
> > > did ubifs driver can achieve "fsync" when user modify some file and
> > > close with save ?
> > 
> > For critical data, you need to call fsync to be sure the data is
> > stored on the flash.
> > There is also a "sync" option for ubifs, but this will hurt performance a lot.
> 
> That reminds me.
> 
> A filesystem-generic "sync-on-close" mount option would be handy for
> things like that.
> 
> Expecting users to call fsync from a shell script is probably a bit much
> in a lot of applications.

Not sure about sync-on-every-close, but ex4-ish
sync-on-close-if-there-was-truncate makes sense, IMO, and we even plan
to implement this, we just do not have enough time ATM:
http://www.linux-mtd.infradead.org/doc/ubifs.html#L_sync_exceptions

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)