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Date: Thu, 5 Feb 2004 16:07:55 -0800
From: Andrew Morton <akpm@osdl.org>
To: Daniel McNeil <daniel@osdl.org>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-aio@kvack.org
Subject: Re: 2.6.2-mm1 aka "Geriatric Wombat" DIO read race still fails
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Daniel McNeil <daniel@osdl.org> wrote:
>
> Andrew,
> 
> I tested 2.6.2-mm1 on an 8-proc running 6 copies of the read_under
> test and all 6 read_under tests saw uninitialized data in less than 5
> minutes. :(

The performance implications of synchronising behind kjournald writes for
normal non-blocking writeback are bad.  Can you detail what you now think
is the failure mechanism?