From owner-freebsd-hackers@FreeBSD.ORG Sat May 17 12:40:15 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 66A1937B401 for ; Sat, 17 May 2003 12:40:15 -0700 (PDT) Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.86.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 825D543FCB for ; Sat, 17 May 2003 12:40:14 -0700 (PDT) (envelope-from phk@phk.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.12.9/8.12.9) with ESMTP id h4HJeCC2007315; Sat, 17 May 2003 21:40:12 +0200 (CEST) (envelope-from phk@phk.freebsd.dk) To: Marcel Moolenaar From: "Poul-Henning Kamp" In-Reply-To: Your message of "Sat, 17 May 2003 12:23:23 PDT." <20030517192323.GA539@athlon.pn.xcllnt.net> Date: Sat, 17 May 2003 21:40:12 +0200 Message-ID: <7314.1053200412@critter.freebsd.dk> cc: freebsd-hackers@freebsd.org Subject: Re: Optimizations. X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 17 May 2003 19:40:15 -0000 In message <20030517192323.GA539@athlon.pn.xcllnt.net>, Marcel Moolenaar writes : >On Sat, May 17, 2003 at 07:14:40PM +0200, Poul-Henning Kamp wrote: >> In message <20030516184626.GB537@athlon.pn.xcllnt.net>, Marcel Moolenaar writes >> : >> >On Fri, May 16, 2003 at 09:59:52AM +0200, Poul-Henning Kamp wrote: >> >> >> >> >That's right:) >> >> >Look at functions in /sys/kern/kern_tc.c. There are so many little >> >> >functions. How about put __inline here and there? >> >> >> >> Try it, and you'll find that things get slower because the code >> >> gets bigger. >> > >> >Observed on what architecture? >> >> i386, but it takes a _lot_ to get a stddev on your measurements >> which allow you to measure this in real-world applications. > >Some are called from hardclock so I can imagine that if inlining has >a positive effect, the effects are generally more indirect. I expect >that (selective) inlining could make a difference on ia64. There's >hardly any ILP now. It's also not important now :-) It all depends on the architecture, and the timecounter hardware. I _really_ think that there are much more low-hanging fruit for optimizing performance, than struggling with MD inlining of functions in the timecounter code. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.