Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262072AbVDLJ2r (ORCPT ); Tue, 12 Apr 2005 05:28:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262075AbVDLJ2r (ORCPT ); Tue, 12 Apr 2005 05:28:47 -0400 Received: from unthought.net ([212.97.129.88]:15545 "EHLO unthought.net") by vger.kernel.org with ESMTP id S262072AbVDLJ2p (ORCPT ); Tue, 12 Apr 2005 05:28:45 -0400 Date: Tue, 12 Apr 2005 11:28:43 +0200 From: Jakob Oestergaard To: Greg Banks Cc: Trond Myklebust , Linux Kernel Mailing List Subject: Re: bdflush/rpciod high CPU utilization, profile does not make sense Message-ID: <20050412092843.GB17359@unthought.net> Mail-Followup-To: Jakob Oestergaard , Greg Banks , Trond Myklebust , Linux Kernel Mailing List References: <20050409213549.GW347@unthought.net> <1113083552.11982.17.camel@lade.trondhjem.org> <20050411074806.GX347@unthought.net> <1113222939.14281.17.camel@lade.trondhjem.org> <20050411134703.GC13369@unthought.net> <1113230125.9962.7.camel@lade.trondhjem.org> <20050411144127.GE13369@unthought.net> <1113232905.9962.15.camel@lade.trondhjem.org> <20050411154211.GG13369@unthought.net> <1113267809.1956.242.camel@hole.melbourne.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1113267809.1956.242.camel@hole.melbourne.sgi.com> User-Agent: Mutt/1.3.28i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1427 Lines: 39 On Tue, Apr 12, 2005 at 11:03:29AM +1000, Greg Banks wrote: > On Tue, 2005-04-12 at 01:42, Jakob Oestergaard wrote: > > Yes, as far as I know - the Broadcom Tigeon3 driver does not have the > > option of enabling/disabling RX polling (if we agree that is what we're > > talking about), but looking in tg3.c it seems that it *always* > > unconditionally uses NAPI... > > I've whined and moaned about this in the past, but for all its > faults NAPI on tg3 doesn't lose packets. It does cause a huge > increase in irq cpu time on multiple fast CPUs. What irq rate > are you seeing? Around 20.000 interrupts per second during the large write, on the IRQ where eth0 is (this is not shared with anything else). [sparrow:joe] $ cat /proc/interrupts CPU0 CPU1 ... 169: 3853488 412570512 IO-APIC-level eth0 ... But still, guys, it is the *same* server with tg3 that runs well with a 2.4 client but poorly with a 2.6 client. Maybe I'm just staring myself blind at this, but I can't see how a general problem on the server (such as packet loss, latency or whatever) would cause no problems with a 2.4 client but major problems with a 2.6 client. -- / jakob - 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/