From mboxrd@z Thu Jan 1 00:00:00 1970 From: jamal Subject: Re: [PATCH 1/4] [NET_SCHED] explict hold dev tx lock Date: Mon, 08 Oct 2007 09:34:50 -0400 Message-ID: <1191850490.4352.41.camel@localhost> References: <1190674298.4264.24.camel@localhost> <1190677099.4264.37.camel@localhost> <20071007.215124.85709188.davem@davemloft.net> Reply-To: hadi@cyberus.ca Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: peter.p.waskiewicz.jr@intel.com, krkumar2@in.ibm.com, johnpol@2ka.mipt.ru, herbert@gondor.apana.org.au, kaber@trash.net, shemminger@linux-foundation.org, jagana@us.ibm.com, Robert.Olsson@data.slu.se, rick.jones2@hp.com, xma@us.ibm.com, gaagaan@gmail.com, netdev@vger.kernel.org, rdreier@cisco.com, mcarlson@broadcom.com, jeff@garzik.org, mchan@broadcom.com, general@lists.openfabrics.org, kumarkr@linux.ibm.com, tgraf@suug.ch, randy.dunlap@oracle.com, sri@us.ibm.com To: David Miller Return-path: Received: from wx-out-0506.google.com ([66.249.82.230]:6982 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750776AbXJHNfF (ORCPT ); Mon, 8 Oct 2007 09:35:05 -0400 Received: by wx-out-0506.google.com with SMTP id h31so1320982wxd for ; Mon, 08 Oct 2007 06:35:04 -0700 (PDT) In-Reply-To: <20071007.215124.85709188.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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