From mboxrd@z Thu Jan 1 00:00:00 1970 From: Charles Subject: ixgbe unstable performance at 1Gb/s Date: Mon, 24 Sep 2012 17:47:19 +0000 (UTC) Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from plane.gmane.org ([80.91.229.3]:35587 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757188Ab2IXRuB (ORCPT ); Mon, 24 Sep 2012 13:50:01 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1TGCnD-0000xq-GP for netdev@vger.kernel.org; Mon, 24 Sep 2012 19:50:03 +0200 Received: from cacheng.unige.ch ([129.194.8.73]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 24 Sep 2012 19:50:03 +0200 Received: from charles.vejnar by cacheng.unige.ch with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 24 Sep 2012 19:50:03 +0200 Sender: netdev-owner@vger.kernel.org List-ID: Hi, I hope I am posting on the right mailing-list. If not, sorry; please redirect me to the right place. Thanks. I have a new motherboard with integrated Intel X540 10GBase-T. For now, I want to use it at 1Gb/s. The bandwidth is only of ~300 Mbit/s (with Iperf). It's actually very unstable (always varies between 100 to 800 Mbit/s during the transfer). If I do "ethtool -K eth1 ntuple on", things are a bit better but still very unstable bandwidth. If I add the kernel parameter "pci=nomsi", everything is fine (and normal, with the same performance, ~950 MBit/s, as a 1Gbit/s NIC). I also run the set_irq_affinity.sh script, w/o noticing a difference. The only weird thing I have found is with ethtoll -S eth1: tx_queue_0_packets: 304262 tx_queue_1_packets: 0 tx_queue_2_packets: 0 tx_queue_3_packets: 1 tx_queue_4_packets: 502939 tx_queue_5_packets: 677967 tx_queue_6_packets: 459869 tx_queue_7_packets: 0 tx_queue_8_packets: 0 tx_queue_9_packets: 0 tx_queue_10_packets: 632626 tx_queue_11_packets: 1719870 tx_queue_12_packets: 0 tx_queue_13_packets: 449811 tx_queue_14_packets: 0 ....... I am using ArchLinux with kernel 3.5.4. Please ask for more details. Any help would be appreciated. Thanks Charles