From mboxrd@z Thu Jan 1 00:00:00 1970 From: Scott Feldman Subject: Re: [E1000-devel] Transmission limit Date: Wed, 01 Dec 2004 08:49:51 -0800 Message-ID: <1101919791.5198.15.camel@localhost.localdomain> References: <1101467291.24742.70.camel@mellia.lipar.polito.it> <41A73826.3000109@draigBrady.com> <16807.20052.569125.686158@robur.slu.se> <1101484740.24742.213.camel@mellia.lipar.polito.it> <41A76085.7000105@draigBrady.com> <1101499285.1079.45.camel@jzny.localdomain> <16811.8052.678955.795327@robur.slu.se> <1101821501.1043.43.camel@jzny.localdomain> <20041130134600.GA31515@xi.wantstofly.org> <1101824754.1044.126.camel@jzny.localdomain> <20041201001107.GE4203@xi.wantstofly.org> <1101863399.4663.54.camel@sfeldma-mobl.dsl-verizon.net> <16813.58484.343629.570703@robur.slu.se> Reply-To: sfeldma@pobox.com Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Lennert Buytenhek , jamal , P@draigBrady.com, mellia@prezzemolo.polito.it, e1000-devel@lists.sourceforge.net, Jorge Manuel Finochietto , Giulio Galante , netdev@oss.sgi.com Return-path: To: Robert Olsson In-Reply-To: <16813.58484.343629.570703@robur.slu.se> Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Wed, 2004-12-01 at 07:34, Robert Olsson wrote: > Nice but I no improvements w. 82546GB @ 133 MHz on 1.6 GHz Opteron it seems. > SMP kernel linux-2.6.9-rc2 > > Vanilla. > 801077pps 410Mb/sec (410151424bps) errors: 95596 > > Patch TXD=4096 > 608690pps 311Mb/sec (311649280bps) errors: 0 Thank you Robert for trying it out. Well those results are counter-intuitive! We remove Tx interrupts and Tx descriptor DMA write-backs and get no re-tries, and performance drops? The only bus activities left are the DMA of buffers to device and the register writes to increment tail. I'm stumped. I'll need to get my hands on a faster system. Maybe there is a bus analyzer under the tree. :-) -scott