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Date: Tue, 24 Jul 2012 18:50:26 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Dave Chinner <david@fromorbit.com>
Cc: Ankit Jain <jankit@suse.de>, Al Viro <viro@zeniv.linux.org.uk>,
        bcrl@kvack.org, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org,
        linux-kernel@vger.kernel.org, Jan Kara <jack@suse.cz>
Subject: Re: [RFC][PATCH] Make io_submit non-blocking
Message-ID: <20120724225026.GA21691@infradead.org>
References: <500E89D1.9010303@suse.de>
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On Wed, Jul 25, 2012 at 08:31:10AM +1000, Dave Chinner wrote:
> FWIW, if you are going to change generic code, you need to present
> results for other filesystems as well (xfs, btrfs are typical), as
> they may not have the same problems as ext4 or react the same way to
> your change. The result might simply be "it is 20% slower"....

And most importantly block devices, as they are one of the biggest
use cases of AIO.  With an almost no-op get_blocks callback I can't
see how this change would provide any gain there.