From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Michel Hautbois Subject: Re: Difficulties to get 1Gbps on be2net ethernet card Date: Wed, 30 May 2012 12:06:28 +0200 Message-ID: References: <1338360536.2760.85.camel@edumazet-glaptop> <1338361587.2760.94.camel@edumazet-glaptop> <1338371774.2760.134.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: netdev To: Eric Dumazet Return-path: Received: from mail-wg0-f44.google.com ([74.125.82.44]:38086 "EHLO mail-wg0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751161Ab2E3KGt (ORCPT ); Wed, 30 May 2012 06:06:49 -0400 Received: by wgbdr13 with SMTP id dr13so4847420wgb.1 for ; Wed, 30 May 2012 03:06:48 -0700 (PDT) In-Reply-To: <1338371774.2760.134.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: 2012/5/30 Eric Dumazet : > On Wed, 2012-05-30 at 11:40 +0200, Jean-Michel Hautbois wrote: > >> I used vmstat in order to see the differences between the two kernels. >> The main difference is the number of interrupts per second. >> I have an average of 87500 on 3.2 and 7500 on 2.6, 10 times lower ! >> I suspect the be2net driver to be the main cause, and I checkes the >> /proc/interrupts file in order to be sure. >> >> I have for eth1-tx on 2.6.26 about 2200 interrupts per second and 23000 on 3.2. >> BTW, it is named eth1-q0 on 3.2 (and tx and rx are the same IRQ) >> whereas there is eth1-rx0 and eth1-tx on 2.6.26. >> > > Might be different coalescing params : > > ethtool -c eth1 > Yes, as stated in my first e-mail, this is different, in 2.6.26 the adaptive-tx coalescing is off, while it is on for 3.4 (sorry, I said 3.2 before but it is 3.4). But I can't change this setting since commit 10ef9ab... JM