From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] [NET] Size listen hash tables using backlog hint
Date: Wed, 18 Oct 2006 20:31:09 -0700 (PDT)
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From: Eric Dumazet Hi <dada1@cosmosbay.com>
Date: Tue, 17 Oct 2006 14:58:37 +0200

> reqsk_queue_alloc() goal is to use a power of two size for the whole
> listen_sock structure, to avoid wasting memory for large backlogs,
> meaning the hash table nr_table_entries is not anymore a power of
> two. (Hence one AND (nr_table_entries - 1) must be replaced by
> MODULO nr_table_entries)

Modulus can be very expensive for some small/slow cpus.  Please round
down to a power-of-2 instead of up if you think the wastage really
matters.

Thanks.