Where and How? Firefox Compile Optimization.

n0rbi666 · Post by **n0rbi666** » Mon Apr 03, 2006 8:04 am

cynric - don't try -Os with gcc-4.1.0 or any gcc 4

It's broken - see this http://forums.gentoo.org/viewtopic-t-43 ... t-250.html thread

(-Os broke my kde, and mozilla-firefox does'nt work when compiled with -Os and gcc 4.1.0 ...)

mrcs · Post by **mrcs** » Mon Apr 03, 2006 11:35 am

n0rbi666 wrote:cynric - don't try -Os with gcc-4.1.0 or any gcc 4 It's broken - see this http://forums.gentoo.org/viewtopic-t-43 ... t-250.html thread

(-Os broke my kde, and mozilla-firefox does'nt work when compiled with -Os and gcc 4.1.0 ...)

I've compiled my whole system with -Os using gcc-4.1 and glibc-2.4 and everything works as expected. The kde stuff I've installed (kdelibs, k3b, kile) compiled just fine, so I guess it's not completely broken?

cynric · Post by **cynric** » Mon Apr 03, 2006 4:43 pm

Hrm. Thanks for the heads up n0rbi666. I think you must have had some other problem at fault though (haven't read the link yet). I have compiled some things as -Os with gcc-4.0 without problems; haven't tried 4.1 yet. I've also heard of many others doing this successfully with KDE. I myself don't run run KDE so that portion isn't a problem.

Vla · Post by **Vla** » Tue Apr 04, 2006 12:21 am

Yes, I compiled my system with -Os and gcc 4.1.0.
KDE, better kdesktop crashed with "-Os -march=athlon-xp -fomit-frame-pointer -ftree-vectorize".
Konqueror and even firefox crashed irregulary. Firefox made me think it could be another probem with a package both depend on.
So i recompiled kdesktop and kdelibs with debugging symbols and using gdb I found out, that jpeg was the problem.
I recompiled it with "-march=athlon-xp -pipe" and all erros are gone. I don't know, if it's -ftree-vectorize oder -Os but I guess it's been -Os.
Hope I could help with this information.

predatorfreak · Post by **predatorfreak** » Tue Apr 04, 2006 12:34 am

Vla wrote:Yes, I compiled my system with -Os and gcc 4.1.0.
KDE, better kdesktop crashed with "-Os -march=athlon-xp -fomit-frame-pointer -ftree-vectorize".
Konqueror and even firefox crashed irregulary. Firefox made me think it could be another probem with a package both depend on.
So i recompiled kdesktop and kdelibs with debugging symbols and using gdb I found out, that jpeg was the problem.
I recompiled it with "-march=athlon-xp -pipe" and all erros are gone. I don't know, if it's -ftree-vectorize oder -Os but I guess it's been -Os.
Hope I could help with this information.

I bet 20 bucks it was -ftree-vectorize.

cynric · Post by **cynric** » Tue Apr 04, 2006 12:42 am

Yeah, it most likely was -ftree-vectorize. I used it for a while, but when recompiling my entire system using gcc-4.1, it said not to use as it causes breakage. Audacious and libVxf86dga both failed to compile with it.

Vla · Post by **Vla** » Tue Apr 04, 2006 1:40 am

Hey, I will give it a shot and let you know!

btw, I don't expect magic from this flag, but I also can't find any kind of benchmark regarding this. I just read on the gcc wiki that this will be improved in next releases... Anyone?

Edit: Damn, you're right. Thought I could have found something on my own

But I'll get my chance

cynric · Post by **cynric** » Tue Apr 04, 2006 2:05 am

Finding benchmarks on any CFLAG configuration is difficult. Even more so to find one not biased; if there is such a thing. -ftree-vectorize is being included in the 4.2 branch so it is no doubt being cleaned up. Glad to see you (Vla) fixed your problem.

KD-120RD · Post by **KD-120RD** » Wed Apr 19, 2006 1:53 am

I played a bit around with -Os the last days. Now my kde is compiled with -Os. I did some benchmarks on kde startup with a stopwatch.
It gave an avarage 3% performance (startup time) win. Not really much, but memory usage went down aswell so I'l keep it.

As the next step I'd like to emerge -eat system, with -Os. I think it would make sense for cpu intense apps to be -03 compiled, as they willl run faster, like gzip or lame. I am unsure with some apps, though.
How about compiling gcc-3.4.x with -O3? Is that a good idea? And how about glibc, or libs in general. What will they benefit most from?

KD-120RD · Post by **KD-120RD** » Thu Apr 27, 2006 12:12 pm

This a little OT, because it has nothing to to with FF anymore, so it will be my last post. (I also switched to konqi now. I miss some extensions, but I will keep it because overall performance is much better).

I am compiling world with -Os right now, but have an extra packages.cflags file for those more cpu intense apps.
I found, that glibc and gcc strip -O3

More about cflags: Cflags Central