From owner-freebsd-current@FreeBSD.ORG Sat Feb 28 18:05:01 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6010216A4CE for ; Sat, 28 Feb 2004 18:05:01 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0D6BE43D1F for ; Sat, 28 Feb 2004 18:05:01 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (localhost [127.0.0.1]) by fledge.watson.org (8.12.10/8.12.10) with ESMTP id i1T23xDL038575; Sat, 28 Feb 2004 21:03:59 -0500 (EST) (envelope-from robert@fledge.watson.org) Received: from localhost (robert@localhost)i1T23xcY038572; Sat, 28 Feb 2004 21:03:59 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Sat, 28 Feb 2004 21:03:58 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: Vincent Poy In-Reply-To: <20040228155420.G8264-100000@oahu.WURLDLINK.NET> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: current@freebsd.org Subject: Re: buildworld times X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 29 Feb 2004 02:05:01 -0000 On Sat, 28 Feb 2004, Vincent Poy wrote: > On Sat, 28 Feb 2004, Robert Watson wrote: > > > On Sat, 28 Feb 2004, Vincent Poy wrote: > > > > > > 2.5 hours seems a little high and would seem to indicate that you're > > > > building world under a kernel that has all the debugging options enabled. > > > > Could you make your kernel config available? > > > > > > Yeah, I recall that -CURRENT on a Mobile PII 366Mhz took the > > > same amount of time so I would imagine the P4 would be faster since I > > > remember PIII running at 800Mhz or so would take about 2 hours and the > > > Athlon K7 at 1.2Ghz was about a little over an hour. I'm using the > > > standard GENERIC kernel and do have the debugging options enabled. > > > > Turning off the debugging options (especially WITNESS) can have a dramatic > > effect on performance. Give it a spin. :-) > > Besides the WITNESS and WITNESS_SKIPSPIN, do these have a big > effect as well? > > options DDB No runtime cost, and useful if anything goes wrong :-). > options INVARIANTS Small but non-zero cost. > options INVARIANT_SUPPORT Space overhead, but other than memory overhead, no run-time cost. > makeoptions DEBUG=-g Makes your kernel build real slow, but won't change the kernel speed. As you point out, debugging problems is a lot easier if you run with INVARIANTS+WITNESS. However, you may well see build times halve or more by running without WITNESS. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Senior Research Scientist, McAfee Research