From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@osdl.org>
Subject: Re: kjournald() with DIO
Date: Thu, 15 Sep 2005 11:52:49 -0700
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Suparna Bhattacharya <suparna@in.ibm.com> wrote:
>
> But I wonder, do we really have to or intend to guarantee DIO vs mmaped
>  write consistency ? What we have is sort of best effort -- we just ensure
>  no corruptions and exposures, and try to keep data consistent to the
>  extent we can.

Yup.  There will be holes where inconsistencies can get in.  We just need
to understand what they are and arrange for them to be as benign as poss.

> Can we actually do a perfect job ?

Certainly we can, but I don't think there's a way of doing it in an
acceptably performant way.