From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Date: Wed, 12 Apr 2006 21:52:46 +0000
Subject: Re: [LARTC] ESFQ not so fair?
Message-Id: <443D76AE.9090905@trash.net>
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References: <443D5449.20706@uznam.net.pl>
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To: lartc@vger.kernel.org

Andy Furniss wrote:
> Corey Hickey changed his esfq to use jhash for dst/src/fw - copy of his
> announce below.
> 
> Andy.
> 
> Corey Hickey wrote:
>> So, I wrote an alternative hash function. It's quite simple, and as long
>> as the range of input values is smaller than the hash table (default
> 1024,
>> up to 16384), collisions will not happen at all. See the updated README
>> file for more details.

Using jhash is a probably a good idea, the "improved" hash is broken
and will cause reordering in some circumstances:

return (h - q->dyn_min) * (q->hash_divisor - 1) / q->dyn_range;

dyn_min, dyn_max and dyn_range, as their name suggests, are adjusted
dynamically, so the hash function changes whenever one of these values
changes, resulting in reordering of packets belonging to a single flow.
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