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From: Daniel Phillips <phillips@bonn-fries.net>
To: Andrea Arcangeli <andrea@suse.de>,
        Daniel Phillips <phillips@bonn-fries.net>
Subject: Re: 2.4.19pre2aa1
Date: Tue, 12 Mar 2002 15:32:44 +0100
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Cc: Rik van Riel <riel@conectiva.com.br>,
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On March 12, 2002 03:25 pm, Andrea Arcangeli wrote:
> On Tue, Mar 12, 2002 at 01:21:35PM +0100, Daniel Phillips wrote:
> > On March 12, 2002 12:47 pm, Andrea Arcangeli wrote:
> > > If it's pure random mul will make no difference to
> > > the distribution. And the closer we're to pure random like in the
> > > wait_table hash, the less mul will help and the more important will be
> > > to just get right the two contigous pages in the same cacheline and
> > > nothing else.
> > 
> > You're ignoring the possibility (probability) of corner cases.  I'm not
> 
> The corner cases cannot go away with a mul.

Oh but they do[1].  If there's a major point you're missing it has to be that.

[1] Not entirely of course, which Bill already pointed out clearly enough.
'Go away' always means 'get less common' with respect to hash functions,
that's the best you can do.

-- 
Daniel
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