lkml.org 
[lkml]   [2003]   [Sep]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: Minimizing the Kernel
From
Date
On Wed, 24 Sep 2003 19:13:28 +0200, Maciej Soltysiak said:
> > Well for starters dont use gcc 3 or above.. code size has increased
> > dramatically with thoose versions. sure they give you more optimization
> Hmm, has anyone tried -Os with gcc3+ ?
> Maybe that'd be good for size optimization?

I've usually been compiling with -Os on gcc3 for a while, works for me.

% size */vmlinux
text data bss dec hex filename
3034134 620847 224824 3879805 3b337d linux-2.6.0-test4-mm6/vmlinux
3476451 621246 227512 4325209 41ff59 linux-2.6.0-test5-mm2/vmlinux
3034632 622210 226360 3883202 3b40c2 linux-2.6.0-test5-mm3/vmlinux
3037706 623409 226360 3887475 3b5173 linux-2.6.0-test5-mm4/vmlinux

-mm6, -mm3, and -mm4 were compiled with -Os, -mm2 with -O2. All with gcc 3.3.1
from RedHat Rawhide. Given how close -mm6, -mm3, and -mm4 are in size, the 12%
or so size saving is almost certainly the efects of -Os rather than changes in
the size of the code. I could rebuild any of them to get an exact number, but
it would take a while on this laptop....
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2005-03-22 13:48    [from the cache]
©2003-2011 Jasper Spaans