From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [patch][rfc] ddds: "dynamic dynamic data structure" algorithm,
 for adaptive dcache hash table sizing (resend)
Date: Tue, 07 Oct 2008 14:06:45 -0700 (PDT)
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From: Nick Piggin <npiggin@suse.de>
Date: Tue, 7 Oct 2008 09:53:09 +0200

> Dcache lookup is partially a tree lookup, but also how do you look up
> entries in a given directory? That is not naturally a tree lookup. Could
> be a per directory tree, though, or a hash, or trie.
> 
> Anyway, I don't volunteer to change that just yet ;)

Historically speaking, the original dcache by Thomas Schoebel-Theuer
(circa 1997) was in fact implemented as a per-directory hash table.

This has all kinds of recursion and other issues, which is why Linus
eventually changed it to use a global hash table scheme.