From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: [NETFILTER] xt_hashlimit : speedups hash_dst()
Date: Fri, 14 Dec 2007 12:20:31 +0100
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Cc: netfilter-devel@vger.kernel.org, netdev@vger.kernel.org
To: Eric Dumazet <dada1@cosmosbay.com>
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Eric Dumazet wrote:
> 1) Using jhash2() instead of jhash() is a litle bit faster if applicable.
> 
> 2) Thanks to jhash, hash value uses full 32 bits.
>    Instead of returning hash % size (implying a divide)
>    we return the high 32 bits of the (hash * size) that will
>    give results between [0 and size-1] and same hash distribution.
> 
>   On most cpus, a multiply is less expensive than a divide, by an order
>   of magnitude.


Clever :) Applied, thanks Eric.