From mboxrd@z Thu Jan 1 00:00:00 1970 From: Badalian Vyacheslav Subject: Re: e1000: Question about polling Date: Wed, 20 Feb 2008 12:25:32 +0300 Message-ID: <47BBF20C.1050706@bigtelecom.ru> References: <20080220075054.GB3885@ff.dom.local> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Jarek Poplawski Return-path: Received: from mail.bigtelecom.ru ([87.255.0.61]:39370 "EHLO mail.bigtelecom.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753820AbYBTJZw (ORCPT ); Wed, 20 Feb 2008 04:25:52 -0500 In-Reply-To: <20080220075054.GB3885@ff.dom.local> Sender: netdev-owner@vger.kernel.org List-ID: Sorry for little information and mistakes in letter. Jesse Brandeburg ask for all my questions. In future i will try to be more accurate then write letters and post more info. Please not think that it disrespect for you. Its simple language barrier =( > On 18-02-2008 10:18, Badalian Vyacheslav wrote: > >> Hello all. >> > > Hi, > > >> Interesting think: >> >> Have PC that do NAT. Bandwidth about 600 mbs. >> >> Have 4 CPU (2xCoRe 2 DUO "HT OFF" 3.2 HZ). >> >> irqbalance in kernel is off. >> >> nat2 ~ # cat /proc/irq/217/smp_affinity >> 00000001 >> nat2 ~ # cat /proc/irq/218/smp_affinity >> 00000003 >> >> Load SI on CPU0 and CPU1 is about 90% >> >> Good... try do >> echo ffffffff > /proc/irq/217/smp_affinity >> echo ffffffff > /proc/irq/218/smp_affinity >> >> Get 100% SI at CPU0 >> >> Question Why? >> > > I think you should show here /proc/interrupts in all these cases. > > >> I listen that if use IRQ from 1 netdevice to 1 CPU i can get 30% >> perfomance... but i have 4 CPU... i must get more perfomance if i cat >> "ffffffff" to smp_affinity. >> >> picture looks liks this: >> 0-3 CPU get over 50% SI.... bandwith up.... 55% SI... bandwith up... >> 100% SI on CPU0.... >> >> I remember patch to fix problem like it... patched function >> e1000_clean... kernel on pc have this patch (2.6.24-rc7-git2)... e1000 >> driver work much better (i up to 1.5-2x bandwidth before i get 100% SI), >> but i think that it not get 100% that it can =) >> > > If some patch works for you, and you can show here its advantages, > you should probably add here some link and request for merging. > > BTW, I wonder if you tried to check if changing CONFIG_HZ makes any > difference here? > > Regards, > Jarek P. > >