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Date: Sat, 22 May 2004 01:11:39 -0700
From: Andrew Morton <akpm@osdl.org>
To: Jens Axboe <axboe@suse.de>
Cc: Chris Mason <mason@suse.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext3 barrier bits
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May as well cc lkml on this.  It's to do with the disk write barrier
implementation.


- How do I know that the barrier code is actually doing stuff?  It doesn't
  seem to affect benchmarks much, if at all.

- Does reiserfs support `mount -o remount,barrier=flush'? and "=none"?

- How do I test the "oh, barriers aren't working" fallback code in ext3?

- Does the kernel tell you if your disk doesn't supoprt barriers?  ie:
  how does the user know if it's working or not?