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Date: Sun, 15 Feb 2009 17:54:27 -0500
From: Theodore Tso <tytso@mit.edu>
To: Fernando Luis =?iso-8859-1?Q?V=E1zquez?= Cao 
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Subject: Re: vfs: Add MS_FLUSHONFSYNC mount flag
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On Sun, Feb 15, 2009 at 04:23:26PM +0900, Fernando Luis Vázquez Cao wrote:
> You mentioned "we should integrate this with the barrier settings". Do
> you imply we should make it a per-device tunable too? Should we keep the
> barrier-related mount options some filesystems provide?
> 

Making barriers to be a per-device tunable makes sense.  The only
reason why we kept it as a mount option in ext4 is for benchmarking
purposes, and in ext3, because the filesystem predated the barrier
code, and there was a desire to be able to benchmark with and without
the old behavior --- and because akpm is still worried about the
performance hit of the barrier code, so he's been resistant about
change the default for ext3.

       	   				- Ted