Rebuilding .src.rpm's for performance

[Adam Bowns <adam-bowns ntlworld com>]

I am considering rebuilding all the rpm's in use on my system so they
are optimised for my processor, but I have a few questions I would
really like to know the answer to before i start :-)

1.Will it increase performance significantly ?
2.Is rpmbuild fully linked into gcc ? Can i use all the flags mentioned
in

http://gcc.gnu.org/onlinedocs/gcc-3.2/gcc/i386-and-x86-64-Options.html#i386%20and%20x86-64%20Options

3.Also, any experiences you have with rebuilding rpm's for athlon-xp
architecture would be of interest to me.


Thanks for your time guys,
Adam