From owner-svn-src-all@FreeBSD.ORG Thu Mar 27 18:12:49 2014 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 88A4B497; Thu, 27 Mar 2014 18:12:49 +0000 (UTC) Received: from mx1.stack.nl (relay04.stack.nl [IPv6:2001:610:1108:5010::107]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "mailhost.stack.nl", Issuer "CA Cert Signing Authority" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 48BCA14D; Thu, 27 Mar 2014 18:12:49 +0000 (UTC) Received: from snail.stack.nl (snail.stack.nl [IPv6:2001:610:1108:5010::131]) by mx1.stack.nl (Postfix) with ESMTP id F2DCEB8069; Thu, 27 Mar 2014 19:12:45 +0100 (CET) Received: by snail.stack.nl (Postfix, from userid 1677) id E0FEB28497; Thu, 27 Mar 2014 19:12:45 +0100 (CET) Date: Thu, 27 Mar 2014 19:12:45 +0100 From: Jilles Tjoelker To: Warner Losh Subject: Re: svn commit: r263778 - in head: bin lib lib/clang sbin share/mk usr.bin usr.sbin Message-ID: <20140327181245.GA69977@stack.nl> References: <201403262230.s2QMUdH6021943@svn.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, Dimitry Andric X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 27 Mar 2014 18:12:49 -0000 On Thu, Mar 27, 2014 at 11:05:00AM -0600, Warner Losh wrote: > On Mar 26, 2014, at 4:30 PM, Dimitry Andric wrote: > > Author: dim > > Date: Wed Mar 26 22:30:38 2014 > > New Revision: 263778 > > URL: http://svnweb.freebsd.org/changeset/base/263778 > > Log: > > Add a SUBDIR_PARALLEL option to bsd.subdir.mk, to allow make to process > > all the SUBDIR entries in parallel, instead of serially. Apply this > > option to a selected number of Makefiles, which can greatly speed up the > > build on multi-core machines, when using make -j. > > This can be extended to more Makefiles later on, whenever they are > > verified to work correctly with parallel building. > Why not have this ‘opt out’ rather than ‘opt in’ like it is now? Are > there any known bad dependencies this introduces? I'm paranoid about build systems ;) It is easy to add dependencies across directories and as long as directories are built in sequence, nothing goes wrong. In fact, I had enabled SUBDIR_PARALLEL in sys/modules/Makefile as well, but this caused mysterious failures with some kernels such as mips ADM5120. -- Jilles Tjoelker