[LinuxBIOS] [Fastboot] Re: [Kboot-general] Re: small 64bit initrd

steve steve at nexpath.com
Sat Jan 14 21:40:08 CET 2006

Thanks hugely for the suggestions.  I need ext3 since this build is also 
used for rebuilding or fixing filesystems but you make a good point.

One of the errors that I made previously, and I appreciate everyone 
pointing out that 2.6 was not necessarily larger than 2.4, is that I did 
not carefully go down each tree in the menuconfig.  At the time I did 
not realize that 2.6 had so many options and buried menus.

I put in the linux-tiny patch for 2.6.14, and after working on the 
config for an hour or so, I got it down to 1020K with gcc-3.3.  Based on 
Eric's suggestions, I took the same config and put it on a system with 
gcc-4.0, put in the -Os option, and got a size of 814K!  This is with 
all I need in the kernel and the kexec option.  If you recall my limit 
is about 950K-960K so this is perfect.  I am assuming the kexec tools 
needs clib so I will have to splice this into busybox somehow but 
hopefully it won't add too much.

I haven't made sure it all works yet, but it is close enough to start 
debugging.  Thanks tremendously for all the help.

Steve G.

Eric W. Biederman wrote:

>The two interesting pieces for your style of configuration are:
>1) The -Os work that has been going on recently, I think I have
>   heard 10% reduction for that.
>2) Careful selection of which compiler you are using as that makes
>   a noticeable difference.
>3) Look under CONFIG_EMBEDDED and possibly elsewhere for options
>   you don't need and can turn off.  CONFIG_EMBEDDED also has some
>   smaller alternatives for some of the common features.
>You might also grab ext2 instead of ext3.  When clean either will

More information about the coreboot mailing list