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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!munnari.OZ.AU!news.ecn.uoknor.edu!news.ysu.edu!news.radio.cz!voskovec.radio.cz!news.radio.cz!CESspool!hammer.uoregon.edu!arclight.uoregon.edu!news.sprintlink.net!news-peer.sprintlink.net!news.sprintlink.net!news-hub.sprintlink.net!news.sprintlink.net!news-fw-6.sprintlink.net!helena.MT.net!nate From: nate@see.my.signature (Nate Williams) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: FreeBSD slower than Linux ? Date: 31 Jan 1997 17:29:59 GMT Organization: SRI Intl. - Montana Operations Lines: 43 Message-ID: <5cta6n$eio@helena.MT.net> References: <dkleinh.854654600@isotope.ps.uci.edu> <5crh6q$44j@synge.maths.tcd.ie> <87iv4ezj3c.fsf@mirriwinni.cse.rmit.edu.au> NNTP-Posting-Host: trout.mt.sri.com Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:34799 In article <87iv4ezj3c.fsf@mirriwinni.cse.rmit.edu.au>, Phillip Musumeci <phillip@rmit.edu.au> wrote: >>>>>> "David" == David Malone <dwmalone@maths.tcd.ie> writes: > >> I'm compiling my program with the stock g77 that comes with each OS. > >> I know Linux is using gcc-2.7.2 and FreeBSD is using gcc-2.6.3 and > >> so I went back to my old Slackware 2.3, which has gcc-2.6.3 and this > >> was still twice as fast. Anyone have any ideas why ? > > David> One thing that it might be is that the FreeBSD maths libraries > David> don't have FPU code in them the way they are distributed, if you > David> recompile them with HAVE_FPU=yes in /etc/make.conf this might > David> make quite a difference for some things. > >Even though this could hurt people without FPUs, maybe we really should >have the standard system optimised for those with FPUs. Umm, no. You can't emulate hardware floating point calls, which is what happens when you compile the libraries with HAVE_FPU. Also, the stock FPU emulator basically 'sucks' (there is the ability of using the GPL one, but it's not used by default due to the GPL). When deciding to make a release, you choose the 'largest compatability' set, not the optimized set. It's really trivial to re-compile the math libraries, probably less so than a long run of the program. :) [ Assuming HAVE_FPU has been uncommented in /etc/make.conf ] # cd /usr/src/lib/libmsun # make depend all install Re-run the application and it should run much faster. Nate -- nate@sri.com | Research Engineer, SRI Intl. - Montana Operations work #: (406) 457-9000 | nate@trout.mt.sri.com | An unfeatured document is a bug. home #: (406) 443-7063 | - John Polstra