On Mon, Mar 19, 2007 at 08:39:52AM +0000, Eur Ing Chris Green wrote: > ... and while there are *some* advantages to running a 64-bit system > there are also downsides still. > > Advantages (that I can remember):- > You can use huge amounts of memory efficiently (i.e. if you have > more than 4Gb or memory) > > Some other things may run more efficiently Where "some other things" mean the vast majority of programs. 64-bit programs (or kernel) on x86_64 has twice as many general purpose registers available as 32-bit programs have and on the register starved i?86 that makes a huge difference. Also, 64-bit programs can use better addressing modes (%rip addressing which removes the need to have a PIC register in shared libraries) and use better calling conventions. On x86_64 generally these advantages measurably overweight the bigger cache and memory footprint (as pointers and long vars in data are now twice as big as for 32-bit programs and even 64-bit code on x86_64 is slightly bigger than 32-bit code). So, unless you rely on binary only kernel drivers that are only available for i686, installing x86_64 distro is a win. Jakub
