Date: Sun, 31 Oct 2004 07:32:14 +0100 (MET)
From: Jan Engelhardt <jengelh@linux01.gwdg.de>
To: linux-kernel@vger.kernel.org
cc: reiser@namesys.com
Subject: Re: readdir loses renamed files
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References: <431547F9-2624-11D9-8AC3-000393CC2E90@iki.fi> <20041025123722.GA5107@thunk.org>
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>>>It should be possible to perform an atomic readdir if that is what you
>>>want to do and if you have space in your process to stuff the result.
>>
>>How much would it cost to always append the new name into the directory rather
>>than modifying it in place?
>
>Forgive me, what does the sentence above mean?  Paste it out of order?

As I have read from earlier replies, ext2/3 replaces a filename with the new
one, given that it is the same length or shorter, and especially that might
skip a while when readdir()ing.
So I was concerned about the speed impact which would arise, if the filename
was never modified in-place but always appended as a new object to the
end-of-directory.


Jan Engelhardt
-- 
Gesellschaft für Wissenschaftliche Datenverarbeitung
Am Fassberg, 37077 Göttingen, www.gwdg.de
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