From owner-svn-src-head@FreeBSD.ORG Wed Jan 21 18:15:18 2015 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 1FED9A3D; Wed, 21 Jan 2015 18:15:18 +0000 (UTC) Received: from cell.glebius.int.ru (glebius.int.ru [81.19.69.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "cell.glebius.int.ru", Issuer "cell.glebius.int.ru" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 7AA958A9; Wed, 21 Jan 2015 18:15:16 +0000 (UTC) Received: from cell.glebius.int.ru (localhost [127.0.0.1]) by cell.glebius.int.ru (8.14.9/8.14.9) with ESMTP id t0LIFC3P080849 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 21 Jan 2015 21:15:12 +0300 (MSK) (envelope-from glebius@FreeBSD.org) Received: (from glebius@localhost) by cell.glebius.int.ru (8.14.9/8.14.9/Submit) id t0LIFC2n080848; Wed, 21 Jan 2015 21:15:12 +0300 (MSK) (envelope-from glebius@FreeBSD.org) X-Authentication-Warning: cell.glebius.int.ru: glebius set sender to glebius@FreeBSD.org using -f Date: Wed, 21 Jan 2015 21:15:12 +0300 From: Gleb Smirnoff To: sbruno@freebsd.org Subject: Re: svn commit: r277213 - in head: share/man/man9 sys/kern sys/ofed/include/linux sys/sys Message-ID: <20150121181512.GE15484@FreeBSD.org> References: <20150120075126.GA42409@kib.kiev.ua> <20150120211137.GY15484@FreeBSD.org> <54BED6FB.8060401@selasky.org> <54BEE62D.2060703@ignoranthack.me> <54BEE8E6.3080009@ignoranthack.me> <54BEEA7F.1070301@ignoranthack.me> <54BEF154.3030606@ignoranthack.me> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54BEF154.3030606@ignoranthack.me> User-Agent: Mutt/1.5.23 (2014-03-12) Cc: Hans Petter Selasky , Adrian Chadd , "src-committers@freebsd.org" , "K. Macy" , Jason Wolfe , "svn-src-all@freebsd.org" , "svn-src-head@freebsd.org" , Konstantin Belousov X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Jan 2015 18:15:18 -0000 Sean, On Tue, Jan 20, 2015 at 04:22:44PM -0800, Sean Bruno wrote: S> In our universe, this commit (right or wrong) resolved our panics. I S> think that there is some room for improvement based on the commentary S> in this thread, but some people do indeed prefer stability over S> performance. I hope we can come to a middle ground somewhere here. Sorry, but this sounds very much like alchemy. We poured this stuff into that stuff and yield in gold precipitate. We don't understand what's going on, but let's record the recipe into our tome of aclhemy wisdom. So alchemy never came to a scientific level, and chemistry evolved as science only when researchers started to measure, explain and understand. If we treat our precious kernel in alchemy way, we will follow the path of alchemy, except that it took centuries for alchemy to die, and for a software product it would take a few years. So, for me Kip ideas sound very sensible. There could be a race somewhere else. You tweak callout subsystem in any direction, timings of events in kernel shift, your race is hidden. If we fix problems w/o understanding them, we are going alchemy way. -- Totus tuus, Glebius.