From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Jones Subject: Re: BCM5704 performance questions. Date: Fri, 10 Jun 2005 15:03:03 -0700 Message-ID: <42AA0E17.8050201@hp.com> References: <42A8E0FE.3020708@candelatech.com> <1118361376.5838.20.camel@rh4> <42A8EBDA.6010306@candelatech.com> <1118363861.5838.29.camel@rh4> <42AA016C.9050801@candelatech.com> <42AA0743.1020101@hp.com> <42AA0C9D.2060006@candelatech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: "'netdev@oss.sgi.com'" Return-path: To: Ben Greear In-Reply-To: <42AA0C9D.2060006@candelatech.com> Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org > There will be a bridge chip, and indeed I see better performance when I just > use a 2-port Intel NIC as opposed to a 4 port, even if I am only actively > using 2 of the 4 ports on the 4-port NIC. For the tg3 hardware I only have a > 4-port NIC. I do assume that a 2-port tg3 NIC w/out a bridge chip would be > faster..but probably not too much. I have been taught by several wise old engineers that the proper spelling of assume is ass-u-me :) Bridge chips can in theory do all sorts of nasty things to performance. > CKO == IP checksum offload? Yes. > Since Dave doesn't want to debug my bridge setup (and I don't blame him), I > am going to try to focus my testing/debug reports on the pktgen tests. > If/when pktgen shows better performance with tg3, I can verify that I see the > same speedups with my proprietary bridging module. I've no idea if CKO would > help or hinder pktgen, nor have I tried to enable or disable it. > >> Are your interface interrupts distributed across the CPUs? > > > I'm using FC2, basically a default install. It does seem to have an irq > balance daemon running. But, I'm not specifically binding IRQs or anything > like that. pktgen tx is running as a single thread, so the rx code could run > mostly on the other CPU if locking allows... again, never ass-u-me. rick