From owner-freebsd-stable Tue Dec 19 9:39:13 2000 From owner-freebsd-stable@FreeBSD.ORG Tue Dec 19 09:39:11 2000 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id 6D27637B400 for ; Tue, 19 Dec 2000 09:39:11 -0800 (PST) Received: (from bright@localhost) by fw.wintelcom.net (8.10.0/8.10.0) id eBJHcxC14987; Tue, 19 Dec 2000 09:38:59 -0800 (PST) Date: Tue, 19 Dec 2000 09:38:58 -0800 From: Alfred Perlstein To: Alessandro de Manzano Cc: stable@freebsd.org Subject: Re: make -j Message-ID: <20001219093858.N19572@fw.wintelcom.net> References: <20001218101613.Y19572@fw.wintelcom.net> <20001219122433.A1961@libero.sunshine.ale> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20001219122433.A1961@libero.sunshine.ale>; from demanzano@iol.it on Tue, Dec 19, 2000 at 12:24:34PM +0100 Sender: bright@fw.wintelcom.net Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG * Alessandro de Manzano [001219 03:25] wrote: > > The rule with -j is that it _should_ work, if it doesn't then try > > without -j and let us know. > > I did a buildworld/buildkernel last week with "-j 8" on my dual celeron system and all, apparently, went fine. > It saved about 30-40% of time. Version 4.2-stable. > > Could someone, please, explain to me why the "-j" stuff could be dangerous ? > It's not much clear to me why doing more then one "cc" (example) at time could break the final object code. > (no flame, it's a very honest question! :-) ) It's possible for incorrectly set up dependancies to cause files to be compiled incorrectly. It's also possible that incorrectly set up dependancies can cause the build to fail. > > 4-8 is good for a single processor with enough ram (gcc is large), > > 4-24 is ok for a SMP box. > > I did with 8 and now trying with 10 (I've only 96Mb RAM) That may be a bit much, if you start swapping because of it that's one way to know you're using too high of a -j. -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] "I have the heart of a child; I keep it in a jar on my desk." To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message