From owner-freebsd-stable@FreeBSD.ORG Fri Oct 19 06:26:30 2007 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 223DE16A417; Fri, 19 Oct 2007 06:26:30 +0000 (UTC) (envelope-from lol@chistydom.ru) Received: from comtv.ru (comtv.ru [217.10.32.17]) by mx1.freebsd.org (Postfix) with ESMTP id 70E8713C455; Fri, 19 Oct 2007 06:26:28 +0000 (UTC) (envelope-from lol@chistydom.ru) X-UCL: actv Received: from yoda.org.ru ([83.167.98.162] verified) by comtv.ru (CommuniGate Pro SMTP 4.1.8) with ESMTP id 7103082; Fri, 19 Oct 2007 10:26:27 +0400 Received: from [80.68.244.40] (adm40.relax.ru [80.68.244.40]) (Authenticated sender: llp@soekris.ru) by yoda.org.ru (Postfix) with ESMTP id 0CE1128BDA; Fri, 19 Oct 2007 10:26:32 +0400 (MSD) Message-ID: <47184DD0.6050704@chistydom.ru> Date: Fri, 19 Oct 2007 10:25:20 +0400 From: Alexey Popov User-Agent: Thunderbird 2.0.0.6 (X11/20070924) MIME-Version: 1.0 To: Scott Long References: <47137D36.1020305@chistydom.ru> <47140906.2020107@FreeBSD.org> <47146FB4.6040306@chistydom.ru> <47147E49.9020301@FreeBSD.org> <47149E6E.9000500@chistydom.ru> <4715035D.2090802@FreeBSD.org> <4715C297.1020905@chistydom.ru> <4715C5D7.7060806@FreeBSD.org> <47165A01.1030806@chistydom.ru> <07289061@ipt.ru> <4717D6BC.5090206@samsco.org> In-Reply-To: <4717D6BC.5090206@samsco.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Boris Samorodov , freebsd-hackers@freebsd.org, freebsd-stable@freebsd.org Subject: Re: amrd disk performance drop after running under high load X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Oct 2007 06:26:30 -0000 Hi Scott Long wrote: >>> interrupt total rate >>> irq6: fdc0 8 0 >>> irq14: ata0 47 0 >>> irq16: uhci0 1428187319 1851 >> ^^^^^^^^^^ ^^^^ [1] >>> irq18: uhci2 12374352 16 >>> irq23: ehci0 3 0 >>> irq46: amr0 11983237 15 >>> irq64: em0 1427141755 1850 >> ^^^^^^^^^^ ^^^^ [2] >>> cpu0: timer 1540896452 1997 >>> cpu1: timer 1542377798 1999 >>> Total 5962960971 7730 >> >> [1] and [2] looks suspicious to me (totals and rate are too close to >> each other and btw to timers). Let the latter (timers) alone. Do you >> use any USB device? Can you try to use other network card? That >> behaviour seems to be an interrupt storm and/or irq collision. > > It's neither. It's a side effect of a feature that FreeBSD abuses for > handling interrupts. Note that amr0 and ehci2 are acting similar. It's > mostly harmless, but it does waste CPU cycles. I wouldn't expect this > on a recent version of FreeBSD, though, at least not from the e1000 > driver. I have this effect on many servers and I believe it is harmless. At once I was trying to reduce CPU usage on the very loaded server and removed USB from kernel. This effect disappeared, but there was no significant difference in CPU usage. I disagree about your words about recent version. I have this effect on many servers with latest FreeBSD-6-stable and em. Actually I have more servers with this effect than without it. With best regards, Alexey Popov