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Date: Sun, 22 Feb 2009 18:19:14 -0500
From: Theodore Tso <tytso@mit.edu>
To: Pavel Machek <pavel@ucw.cz>
Cc: Eric Sandeen <sandeen@redhat.com>, Jan Kara <jack@suse.cz>,
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       Ric Wheeler <rwheeler@redhat.com>
Subject: Re: vfs: Add MS_FLUSHONFSYNC mount flag
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On Sun, Feb 22, 2009 at 03:15:33PM +0100, Pavel Machek wrote:
> 
> Sounds like posix violation to
> me... '/sys/fsync_does_not_really_sync'?

It's as much a Posix violation as noatime.  :-)

> Perhaps it is better done at glibc level? Environment variables
> already mostly have semantics you want.....

Environment variables own't allow us to switch fsync's on and off
while the process is running, so that the system can run "safe" while
it is on AC mains, but "low power" when on battery.

      	    	       	    	   	   - Ted