From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Sandeen <sandeen@redhat.com>
Subject: Re: Unable to disable barriers
Date: Wed, 30 Jul 2008 11:37:40 -0500
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Cc: "linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>,
	Theodore Tso <tytso@mit.edu>
To: Gary Hawco <ghawco@cox.net>
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Gary Hawco wrote:
> Subject pretty much says it all.
> 
> For testing purposes I tried to disable barriers in fstab (barriers=0).  On
> reboot the filesystem will not mount read/write until barriers are reenabled.

What errors do you get?

> This occurs whether I use ordered data mode or data writeback mode, in both
> Gentoo and Slackware 12.1
> 
> Is this behavior by design (that barriers can not be disabled)?
> 
> Thanks,
> Gary

Hm, it's not supposed to be :)

Perhaps you just spelled it wrong:

root@inode ~]# mount -o barriers=0 /dev/sdb2 /mnt/test
mount: wrong fs type, bad option, bad superblock on /dev/sdb2,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

[root@inode ~]# mount -o barrier=0 /dev/sdb2 /mnt/test
[root@inode ~]#

-Eric