From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/11480 Path: news.gmane.org!.POSTED!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: more fun with non-Linux Linux ABI Date: Wed, 14 Jun 2017 20:15:13 -0400 Message-ID: <20170615001513.GL1627@brightrain.aerifal.cx> References: <20170611180158.GS30784@example.net> <20170611215020.GB1627@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: blaine.gmane.org 1497485728 7810 195.159.176.226 (15 Jun 2017 00:15:28 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Thu, 15 Jun 2017 00:15:28 +0000 (UTC) User-Agent: Mutt/1.5.21 (2010-09-15) To: musl@lists.openwall.com Original-X-From: musl-return-11493-gllmg-musl=m.gmane.org@lists.openwall.com Thu Jun 15 02:15:23 2017 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by blaine.gmane.org with smtp (Exim 4.84_2) (envelope-from ) id 1dLIRW-0001ms-II for gllmg-musl@m.gmane.org; Thu, 15 Jun 2017 02:15:22 +0200 Original-Received: (qmail 1965 invoked by uid 550); 15 Jun 2017 00:15:26 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 1944 invoked from network); 15 Jun 2017 00:15:25 -0000 Content-Disposition: inline In-Reply-To: Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:11480 Archived-At: On Mon, Jun 12, 2017 at 08:29:59AM -0700, Bobby Powers wrote: > On Sun, Jun 11, 2017 at 2:50 PM, Rich Felker wrote: > >> Such an option would most probably result in a pretty small performance > >> impact on modern (native) Linux. > > > > It's actually a pretty large impact; recent (4.x+ IIRC) versions of > > GNU makes are considerably slower because they dropped use of vfork > > and switched to fork rather than making it use posix_spawn like it > > should. > > Do you know why they chose not to use posix_spawn? Probably lack of knowledge, or lack of resources to test a major change like that. Possibly missing functionality they want to do between fork and exec, but it seems like they could use posix_spawn for the cases where they don't need extra functionality and fallback to fork+exec when they do. You'd have to follow up with the GNU make project to know for sure. Rich