From owner-cvs-all Thu Apr 4 3:37: 0 2002 Delivered-To: cvs-all@freebsd.org Received: from wantadilla.lemis.com (wantadilla.lemis.com [192.109.197.80]) by hub.freebsd.org (Postfix) with ESMTP id 6DE9237B416; Thu, 4 Apr 2002 03:36:52 -0800 (PST) Received: by wantadilla.lemis.com (Postfix, from userid 1004) id 5103B7841C; Thu, 4 Apr 2002 12:08:05 +0930 (CST) Date: Thu, 4 Apr 2002 12:08:05 +0930 From: Greg 'groggy' Lehey To: Dag-Erling Smorgrav Cc: Kenneth Culver , Matthew Dillon , Mike Barcroft , "M. Warner Losh" , jake@locore.ca, cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG Subject: Re: style(9) bike shed, 371st edition (was: cvs commit: src/sys/i386/i386 critical.c src/sys/i386/include cpufunc.h critical.h src/sys/i386/isa apic_vector.s icu_vector.s src/sys/kern kern_fork.c kern_proc.c kern_switch.c src/sys/alpha/alph) Message-ID: <20020404120805.U44513@wantadilla.lemis.com> References: <20020402154308.F46914-100000@alpha.yumyumyum.org> <20020403100131.Q26122@wantadilla.lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.3.23i Organization: The FreeBSD Project Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-418-838-708 WWW-Home-Page: http://www.FreeBSD.org/ X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wednesday, 3 April 2002 at 15:30:18 +0200, Dag-Erling Smorgrav wrote: > Greg 'groggy' Lehey writes: >> On Tuesday, 2 April 2002 at 23:31:38 +0200, Dag-Erling Smorgrav wrote: >>> Using spaces instead of tabs, especially in headers, has a noticeable >>> (negative) impact on compilation speed. >> Do you have figures? > > No. I benchmarked this a long time ago on C++ sources using Sun's > compiler suite; the difference was noticeable but the sample was > small. Once upon a time, the lexical analysis really did take up a significant part of the compiler's time. But nowadays faster processors make it easier to use more time-consuming code generation algorithms, and I suspect that lexical analysis falls into the noise anyway. It would be interesting if somebody would examine it. On a similar note, Andrew Tridgell has written a compiler cache which claims to be able to speed up things by recognizing already-compiled sources. I'm a little sceptical myself, but everybody who has tried it says it's very useful. http://ccache.samba.org/ for more details. Greg -- See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message