From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH] ifb: add multi-queue support
Date: Mon, 16 Nov 2009 08:39:05 -0800
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On Fri, 13 Nov 2009 12:37:07 +0800
Changli Gao <xiaosuo@gmail.com> wrote:

> ifb: add multi-queue support
> 
> Add multi-queue support, and one kernel thread is created for per queue.
> It can used to emulate multi-queue NIC in software, and distribute work
> among CPUs.

My $.02 is that receive packet steering RPS should be done generically at
receive layer. Then all the CPU, mapping and configuration issues can be
done once, not just for IFB, Bridge, VLAN, ... The number of users of IFB
is small, and setup is complex. Steering packets in IFB is optimizing only
a rarely used corner.

Layered link services like IFB need to be multi-threaded lockless to maintain
the advantages of multi-queue and RPS.

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