Re: Kernel bloat 2.4 vs. 2.5

[Andrew Morton <akpm@digeo.com>]

Chris Wedgwood <cw@f00f.org> wrote:
>
> On Tue, Mar 04, 2003 at 03:41:05PM -0800, Andrew Morton wrote:
> 
> > Daniel Egger <degger@fhm.edu> wrote:
> 
> > > I've seen surprisingly few messages about the dramatic size
> > > increase between a simple 2.4 and a 2.5 kernel image.
> 
> > 2.4 has magical size reduction tricks in it which were not brought
> > into 2.5 because we expect that gcc will do it for us.
> 
> I can't see it helping *that* much, for me I have:
> 
>     charon:~/wk/linux% size 2.4.x-cw/vmlinux bk-2.5.x/vmlinux
>        text    data     bss     dec     hex filename
>     2003887  120260  191657 2315804  23561c 2.4.x-cw/vmlinux
>     2411323  267551  181004 2859878  2ba366 bk-2.5.x/vmlinux
> 
>     gcc version 2.95.4 20011002 (Debian prerelease)
> 
> this is for functionally (in terms of .config) equivalent kernels.
> 

Don't know what your point is here, really.

2.4 has hacks to make it smaller.  iirc they were worth ~200 kbytes, or
around 10%.

gcc-3.x string sharing was supposed to make those hacks unnecesary.  However
a quick test here shows gcc-3.2.1 generating a 10% larger 2.5 image than
gcc-2.95.3, so a club may need to be taken to 2.5 as well.