Rebuilding packages with -march=native flag (Intel Haswell 4770K)

Olaus · 03-10-2014, 05:40 AM

Hi, I am thinking of rebuilding some (I guess not all) Slackware64-14.1 packages with the CFLAG -march=native for my machine (Core i7 Haswell 4770K).
What packages would be good candidates to improve speed?
Gimp maybe, to speed up graphical processing?
The whole /a directory?

I am rebuilding Chromium right now, but it seems to take some time...
I will also try https://github.com/graysky2/kernel_gcc_patch to optimize the kernel.

Olaus · 03-10-2014, 07:12 AM

Quote:

Originally Posted by Olaus

Hi, I am thinking of rebuilding some (I guess not all) Slackware64-14.1 packages with the CFLAG -march=native for my machine (Core i7 Haswell 4770K).
What packages would be good candidates to improve speed?
Gimp maybe, to speed up graphical processing?
The whole /a directory?

I am rebuilding Chromium right now, but it seems to take some time...
I will also try https://github.com/graysky2/kernel_gcc_patch to optimize the kernel.

Should I perhaps rebuild Mesa first before rebuilding Gimp/Chromium/anything else needing a GUI?

Nh3xus · 03-10-2014, 07:28 AM

According to some Slackware gurus out there, it's a good idea to rebuild all the glibc related packages first.

The speed increase will affect the overall system then.

I've picked that fact from another similar thread but I forgot the link.

rogan · 03-10-2014, 10:26 AM

I've tried rebuilding firefox and seamonkey with march=native on an 4430 i5 but the build crashes in the
finishing stages (some python test that barfs) on both packages. Used to work ok on my old amd phenom though.
Because of this I do not dare A glibc rebuild. Please let us know if all goes well.

moisespedro · 03-10-2014, 10:35 AM

I've seen people suggesting rebuilding glib,glib2 and glibc

genss · 03-10-2014, 11:04 AM

Quote:

Originally Posted by Nh3xus

According to some Slackware gurus out there, it's a good idea to rebuild all the glibc related packages first.

The speed increase will affect the overall system then.

I've picked that fact from another similar thread but I forgot the link.

i forgot to mention there
glibc is a heavy case of cpu dispatching, so recompiling it won't make any difference (since it always uses the fastest functions)
if done wrong it could even hurt (if it gets confused and starts falling back to "safe" functions)

heavy things might benefit from optimization
like a browser or maybe even xorg (O3 or Os ? hmmmm)

PS benchmarks, benchmarks, benchmarks

Olaus · 03-26-2014, 06:45 AM

Quote:

Originally Posted by Olaus

Hi, I am thinking of rebuilding some (I guess not all) Slackware64-14.1 packages with the CFLAG -march=native for my machine (Core i7 Haswell 4770K).
What packages would be good candidates to improve speed?
Gimp maybe, to speed up graphical processing?
The whole /a directory?

I am rebuilding Chromium right now, but it seems to take some time...
I will also try https://github.com/graysky2/kernel_gcc_patch to optimize the kernel.

Both Chromium from Alien's repository and my version compiled with -march native gets about 7,500 points at http://peacekeeper.futuremark.com/, so I guess there was not much, if any gain?

moisespedro · 03-26-2014, 07:27 AM

I don't see much gain on it, either. I still set march to native on any SlackBuild I use tho.