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From: David Miller <davem@davemloft.net>
Subject: Re: rps perfomance WAS(Re: rps: question
Date: Thu, 15 Apr 2010 01:57:56 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 14 Apr 2010 22:57:41 +0200

> RPS can be tuned (Changli wants a finer tuning...), it would be
> intereting to tune multiqueue devices too. I dont know if its possible
> right now.

Only NIU allows real detailed control over queue selection and
stuff like that, because the hardware has a real TCAM for
packet matching and packets which match in TCAM entries can
steer to different collections of queues.

We have ethtool interfaces for this (ETHTOOL_GRXCLS*), so you can
change it.

For most other chips we only have interfaces for modifying the
RX hashing algorithm or what the RX hash covers, stuff like
that.

See also ETHTOOL_GRXFH, ETHTOOL_SRXFH, ETHTOOL_SRXNTUPLE, and
ETHTOOL_GRXNTUPLE, the latter two of which were added for Intel
NICs.