From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 20 Mar 2003 18:44:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 20 Mar 2003 18:43:43 -0500 Received: from holly.csn.ul.ie ([136.201.105.4]:8148 "EHLO holly.csn.ul.ie") by vger.kernel.org with ESMTP id ; Thu, 20 Mar 2003 18:43:29 -0500 Date: Thu, 20 Mar 2003 23:54:21 +0000 (GMT) From: Mel Gorman X-X-Sender: mel@skynet To: Linux Kernel Mailing List Subject: Poor performance with pcnet32 on SMP Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I have being noticing some seriously poor network performance with SMP enabled. The machine is a xSeries 350 with quad xeon procesors. Under UP, I get decent transfer rates but with SMP enabled, it won't get over 2kB/s. I tried binding interrupts to one processor with echo 1 > /proc/irq/16/smp_affinity which, according to mail archives fixed the problem for other people, but the result is the same. A CVS checkout from a server on the local lan of a source tree less than 1MB took over an hour to complete but under UP completes in about 2 seconds. This occurs with both 2.4.20 and 2.5.64. In case it is relevant, the dmesg output related to the card on 2.5.64 is pcnet32.c:v1.27b 01.10.2002 tsbogend@alpha.franken.de pcnet32: PCnet/FAST III 79C975 at 0x2200, 00 02 55 fc 6d 21 assigned IRQ 16. eth0: registered as PCnet/FAST III 79C975 pcnet32: 1 cards_found. eth0: link up, 10Mbps, half-duplex, lpa 0x0021 Module pcnet32 cannot be unloaded due to unsafe usage in include/linux/module.h:457 Any suggestions on how to fix this are appreciated -- Mel Gorman