netdev - Re: [PATCH 1/4]: net: Allow RX queue selection to seed TX queue hashing.

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Date:	Thu, 29 Jan 2009 08:31:41 +1100
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	David Miller <davem@...emloft.net>
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH 1/4]: net: Allow RX queue selection to seed TX queue
	hashing.

On Wed, Jan 28, 2009 at 12:22:31PM -0800, David Miller wrote:
>
> No matter what you think about the randomness aspect, our
> divide avoidance technique being used here will still
> get in the way of the situations you seem to be concerned
> about.
> 
> We do the jhash et al. magic in order to be able to use a
> multiply to get the modulus.  So the function computing from
> RX to TX queue numbers will never be straightforward.

Right, if the number of queues weren't equal then clearly it's
not an issue to tack on more randomness.  But I was thinking of
scenarios where you have two identical NICs, performing routing
where the number of queues is likely to be identical.

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
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