Date: Thu, 13 Mar 2008 20:02:24 +0800 From: Julius Huang <juliushuang@gmail.com> To: Luca Presotto <Luca.Presotto@cern.ch> Cc: marcin.koziuk@planet.nl, freebsd-questions@freebsd.org Subject: Re: Tuning make.conf Message-ID: <87F851FC-750A-478F-BD01-1B7FED69BF7A@gmail.com> In-Reply-To: <9A6A62B6B84859469F3EBB5F09D818CA219E98@cernxchg50.cern.ch> References: <Pine.LNX.4.58.0803130937530.5944@lxplus098.cern.ch> <47D9004D.5070407@planet.nl> <9A6A62B6B84859469F3EBB5F09D818CA219E98@cernxchg50.cern.ch>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi, On Mar 13, 2008, at 18:58 , Luca Presotto wrote: >> You're *really* wasting your time. > I supposed that! > > >> Your system is doing no cpu cycles at all for most of >> the time anyway. [cut]Also, makeopts and -pipe just make >> _compiling_ faster, not the >> applications themselves!!!. > > I agree with everything. In any case I think that a faster > compiling will really be a good thing. > I have been reading another time the man of make.conf and I still > have some doubts. > Neither in the example either in the man page there is any > reference to "MAKEOPTS". Changing from -j1 to -j3 would really be a > huge difference! > Isn't -j depend on how many cpu/core and a faster harddisk / raid? In our small lab we used to install New system on some Very Old SCSI for testing (18G SCSI 2 I think). It takes 2x to 3x more time to build world / kernel than a New SCSI Ultra 320 HD on the Same machine no matter what we put in -j. Faster / Higher IO through put always compile faster. Also there may be problem buildworld and buildkernel if use -j IIRC, other method is required to speed up compiler when build world / kernel. Like not compile everything except what is Really need to be recompile. > To be able to set this is very important. > Then I don't want an ultra tweaked make.conf like gentooers do. > Just a reasonable one. > (And you have convinced me, I won't recompile everything. Just to > have a good compiling when I will be upgrading) > > I have some doubts about the correct syntax, the man is ambiguous > in this point. > If I write CPUTYPE= core2 will it automatically sets all the best > safe CFLAGS for my core or just set the -march=core2 > Should my make.conf be like: > MAKEOPTS==-j3 > CPUTYPE=core2 > CFLAGS= --O2 -pipe -fno-strict-aliasing > > or just: > MAKEOPTS==-j3 > CPUTYPE=core2 > > or maybe: > > MAKEOPTS==-j3 > CPUTYPE=core2 > CFLAGS+= --O2 -pipe -fno-strict-aliasing > I remember seeing some thread in Stable@, Question@, Performance@ discuss about best CPUTYPE on AMD64 not long ago. J.H. >> Please take a look at the following pages, they have a lot more >> information about this matter ;) >> http://funroll-loops.info/ >> http://bugs.gentoo.org/show_bug.cgi?id=74072 > > Actually that's really funny!! I think that's why there are so many > pages about gentoo and almost none about other OSes. > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions- > unsubscribe@freebsd.org"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?87F851FC-750A-478F-BD01-1B7FED69BF7A>