From: Ted Ts'o <tytso@mit.edu>
Subject: Re: ext4: Fix data corruption with multi-block writepages support
Date: Mon, 7 Feb 2011 12:45:52 -0500
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To: Matt <jackdachef@gmail.com>
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On Fri, Feb 04, 2011 at 10:40:47PM +0000, Matt wrote:
> 
> So that means that the file-corruption which existed until 2.6.37-rc6
> and got triggered (for me) more easily via "dm crypt: scale to
> multiple CPUs"
> is fixed now ?

Well, a patch exists for it that will be merged into 2.6.38.

> That should give ext4 a nice speedup for >=2.6.38 :)

I'm not going to make it be the default for 2.6.38, since it's fairly
late in the -rc features.  People who want it can explicitly enable it
using the mount option mblk_io_submit, though.  (And let me know your
success stories!  :-) I will be enabling it as the default in
2.6.39-rc1.

> Reported-by: Matthias Bayer <jackdachef <at> gmail <dot> com >

Sure!

						- Ted