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Date: Fri, 24 May 2002 13:04:33 -0400 (EDT)
From: Alexander Viro <viro@math.psu.edu>
To: Andrea Arcangeli <andrea@suse.de>
cc: Linus Torvalds <torvalds@transmeta.com>, linux-kernel@vger.kernel.org
Subject: Re: negative dentries wasting ram
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On Fri, 24 May 2002, Andrea Arcangeli wrote:

> > Note that this will have to touch the FS anyway, since the O_CREAT thing
> > forces a call down to the FS to actually create the file.
> 
> yep. the only case where it could provide some in-core "caching"
> positive effect is:
> 
> 	unlink
> 	open(w/o creat)
> 
> but I don't see it as a common case.

	Guys, how about tracing the damn thing and checking what actually
happens?  Or, at least, checking the prototypes and noticing that ->create()
takes (hashed) dentry as an argument, so if unlinked on had been freed we _must_
call ->lookup().