Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262608AbUCaWhA (ORCPT ); Wed, 31 Mar 2004 17:37:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262547AbUCaWg7 (ORCPT ); Wed, 31 Mar 2004 17:36:59 -0500 Received: from mail1.slu.se ([130.238.96.11]:36575 "EHLO mail1.slu.se") by vger.kernel.org with ESMTP id S262608AbUCaWg5 (ORCPT ); Wed, 31 Mar 2004 17:36:57 -0500 From: Robert Olsson MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16491.18384.536778.338660@robur.slu.se> Date: Thu, 1 Apr 2004 00:36:00 +0200 To: Andrea Arcangeli Cc: Dipankar Sarma , Robert Olsson , "David S. Miller" , kuznet@ms2.inr.ac.ru, linux-kernel@vger.kernel.org, netdev@oss.sgi.com, paulmck@us.ibm.com, akpm@osdl.org Subject: Re: route cache DoS testing and softirqs In-Reply-To: <20040331212817.GQ2143@dualathlon.random> References: <20040329222926.GF3808@dualathlon.random> <200403302005.AAA00466@yakov.inr.ac.ru> <20040330211450.GI3808@dualathlon.random> <20040330133000.098761e2.davem@redhat.com> <20040330213742.GL3808@dualathlon.random> <20040331171023.GA4543@in.ibm.com> <16491.4593.718724.277551@robur.slu.se> <20040331203750.GB4543@in.ibm.com> <20040331212817.GQ2143@dualathlon.random> X-Mailer: VM 7.17 under Emacs 21.3.1 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1060 Lines: 28 Andrea Arcangeli writes: > Maybe the problem is simply that NAPI should be tuned more aggressively, > it may have to poll for a longer time before giving up. It cannot poll much more... 20 Million packets were injected in total there were 250 RX irq's. Most from my ssh sessions. There are some TX interrupts... it's another story Packet flooding is just our way to generate load and kernel locking must work with and without irq's. As far as I understand the real problem is when do_softirq is run from irqexit etc. Some thoughts... If we tag the different do_softirq sources (look in my testpatch) we can control the softirqs better. For example; do_softirq's from irqexit etc could be given low a "max_restart" this to move processing to ksoftird maybe even dynamic. Cheers. --ro - 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/