Subject: Re: [PATCH 1/4] [NET_SCHED] explict hold dev tx lock

From: jamal <[email-masked]>
Date: Mon, 08 Oct 2007 09:34:50 -0400

On Sun, 2007-07-10 at 21:51 -0700, David Miller wrote:

> For these high performance 10Gbit cards it's a load balancing
> function, really, as all of the transmit queues go out to the same
> physical port so you could:
> 
> 1) Load balance on CPU number.
> 2) Load balance on "flow"
> 3) Load balance on destination MAC
> 
> etc. etc. etc.

The brain-block i am having is the parallelization aspect of it.
Whatever scheme it is - it needs to ensure the scheduler works as
expected. For example, if it was a strict prio scheduler i would expect
that whatever goes out is always high priority first and never ever
allow a low prio packet out at any time theres something high prio
needing to go out. If i have the two priorities running on two cpus,
then i cant guarantee that effect.
IOW, i see the scheduler/qdisc level as not being split across parallel
cpus. Do i make any sense?

The rest of my understanding hinges on the above, so let me stop here.

cheers,
jamal