From mboxrd@z Thu Jan  1 00:00:00 1970
From: Asdo <asdo@shiftmail.org>
Subject: Re: Why does one get mismatches?
Date: Sat, 20 Feb 2010 12:12:39 +0100
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To: Goswin von Brederlow <goswin-v-b@web.de>
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Goswin von Brederlow wrote:
> The check is usualy done with the filesystem mounted and in use. So one
> case would be that the block got written, changed and then checked
> before the FS decided to flush the dirty block again.
>
> The other scenario suggested in the past is that the block was written,
> changed and then the file deleted, making the block unused, 
This is not enough to cause the problem if I understand correctly, it 
also needs to change value at this point, right?
So how can it change value... is the same buffer used for another block?
> before it
> got flushed again. The filesystem then sees no need to write a dirty but
> unused block so it never gets rewritten. It never gets read either so
> that  is safe.
>