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Date: Tue, 3 Sep 2002 13:33:20 -0300 (BRT)
From: Rik van Riel <riel@conectiva.com.br>
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To: "Peter T. Breuer" <ptb@it.uc3m.es>
Cc: root@chaos.analogic.com, linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] mount flag "direct" (fwd)
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On Tue, 3 Sep 2002, Peter T. Breuer wrote:

> > How does the other user's of this device "know" that there is
> > a new file so it can update its notion of the block-device state?
>
> The block device itself is stateless at the block level. Every block
> access goes "direct to the metal".
>
> The question is how much FS state is cached on either kernel.
> If it is too much, then I will ask how I can cause to be less, perhaps
> by use of a flag that parallels how O_DIRECT works.  I thought that new
> files were entries in a directories inode and I agree that inodes are
> held in memory!  But I don't know when they are first read or reread.

And neither can you know.  After all, this is filesystem dependant.

You cannot decide whether filesystem-independant clustering is
possible unless you know that all the filesystems play by your
rules.  So much for filesystem-independance.

regards,

Rik
-- 
	http://www.linuxsymposium.org/2002/
"You're one of those condescending OLS attendants"
"Here's a nickle kid.  Go buy yourself a real t-shirt"

http://www.surriel.com/		http://distro.conectiva.com/

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