From owner-freebsd-stable@FreeBSD.ORG Tue Oct 13 07:58:31 2009 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 D9F5C1065676 for ; Tue, 13 Oct 2009 07:58:31 +0000 (UTC) (envelope-from serenity@exscape.org) Received: from ch-smtp01.sth.basefarm.net (ch-smtp01.sth.basefarm.net [80.76.149.212]) by mx1.freebsd.org (Postfix) with ESMTP id 922208FC17 for ; Tue, 13 Oct 2009 07:58:31 +0000 (UTC) Received: from c83-253-248-99.bredband.comhem.se ([83.253.248.99]:52838 helo=mx.exscape.org) by ch-smtp01.sth.basefarm.net with esmtp (Exim 4.68) (envelope-from ) id 1MxcGr-0005f9-4Z; Tue, 13 Oct 2009 09:58:15 +0200 Received: from [192.168.1.5] (macbookpro [192.168.1.5]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mx.exscape.org (Postfix) with ESMTPSA id 8A443E736; Tue, 13 Oct 2009 09:58:11 +0200 (CEST) Mime-Version: 1.0 (Apple Message framework v1076) Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes From: Thomas Backman In-Reply-To: <20091012223529.GA77733@onelab2.iet.unipi.it> Date: Tue, 13 Oct 2009 09:58:09 +0200 Content-Transfer-Encoding: 7bit Message-Id: <3C775420-9B3D-4971-BDA8-4D2FD507587F@exscape.org> References: <20091012223529.GA77733@onelab2.iet.unipi.it> To: Luigi Rizzo X-Mailer: Apple Mail (2.1076) X-Originating-IP: 83.253.248.99 X-Scan-Result: No virus found in message 1MxcGr-0005f9-4Z. X-Scan-Signature: ch-smtp01.sth.basefarm.net 1MxcGr-0005f9-4Z 4b657c0df64226fd8f11ffc7a4235081 Cc: freebsd-stable Subject: Re: Extreme console latency during disk IO (8.0-RC1, previous releases also affected according to others) 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: Tue, 13 Oct 2009 07:58:31 -0000 On Oct 13, 2009, at 12:35 AM, Luigi Rizzo wrote: > On Mon, Oct 12, 2009 at 09:48:42PM +0200, Thomas Backman wrote: >> I'm copying this over from the freebsd-performance list, as I'm >> looking for a few more opinions - not on the problems *I* am having, >> but rather to check whether the problem is universal or not, and if >> not, find a possible common factor. >> In other words: I want to hear about your experiences, *good or bad*! >> >> Here's the original thread (not from the beginning, though): >> http://lists.freebsd.org/pipermail/freebsd-performance/2009-October/003843.html >> >> Long story short, my version: when the disk is stressed hard enough, >> console IO becomes COMPLETELY unbearable. 10+ seconds to switch >> between windows in screen(1), running (or even typing) simple >> commands, etc. This happens both via SSH and the serial console. > > hi, > this issue (not specific to FreeBSD, and not new -- it has been > like this forever) is discussed in some detail here > > http://www.bsdcan.org/2009/schedule/events/122.en.html > > The following code (a bit outdated) can help > > http://lists.freebsd.org/pipermail/freebsd-stable/2009-March/048704.html > > cheers > luigi Hmm, how stable would you say the code is? (And/or has there been any progress since March?) I'd prefer something that I feel confident in using in production, and the warning in the README clearly says "stay away!". Regards, Thomas