From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Willstrand" Subject: Re: Bad network performance over 2Gbps Date: Tue, 15 Apr 2008 22:15:14 +0200 Message-ID: <175f5a0f0804151315x1e192fc7p7dac1e84fd154211@mail.gmail.com> References: <1208282804.23631.27.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: "Anton Titov" , netdev@vger.kernel.org Return-path: Received: from el-out-1112.google.com ([209.85.162.177]:5818 "EHLO el-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754298AbYDOUPR (ORCPT ); Tue, 15 Apr 2008 16:15:17 -0400 Received: by el-out-1112.google.com with SMTP id n30so316559elf.21 for ; Tue, 15 Apr 2008 13:15:16 -0700 (PDT) In-Reply-To: <1208282804.23631.27.camel@localhost> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: [Changed mail list] On Tue, Apr 15, 2008 at 8:06 PM, Anton Titov wrote: > I use Linux for serving a huge amount of static web on few servers. When > network traffic goes above 2Gbit/sec ksoftirqd/5 (not every time 5, but > every time just one) starts using exactly 100% CPU time and packet > packet loss starts preventing traffic from going up. When the network > traffic is lower than 1.9Gbit ksoftirqds use 0% CPU according to top. > > Uplink is 6 gigabit Intel cards bonded together using 802.3ad algorithm > with xmit_hash_policy set to layer3+4. On the other side is Cisco 2960 > switch. Machine is with two quad core Intel Xeons @2.33GHz. > > Here goes a screen snapshot of "top" command. The described behavior > have nothing to do with 13% io-wait. It happens even if it is 0% > io-wait. > http://www.titov.net/misc/top-snap.png > > kernel configuration: > http://www.titov.net/misc/config.gz > > /proc/interrupts, lspci, dmesg (nothing intresting there), ifconfig, > uname -a: > http://www.titov.net/misc/misc.txt.gz > > Is it a Linux bug or some hardware limitation? > > Regards, > Anton Titov > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >