Lilypond speed

[hernan]

My main frustration with Lilypond is speed. In my setup (Win-XP, P4 3.0Ghz, 1G
ram) to process a fairly simple scoresheet (2 or 3 pages) it takes about 8
seconds. That might not seem a great deal, but it is really annoying when one is
doing lots of retouching (edit one bit, compile, see results, edit again... 
etc) 

Is there some recipe to speed things up? Are the performance bottlenecks
identified? 

I read in the main.cc source that the GUILE start-up is very time consumming. I
wonder if some modification in the code could be done so that the GUILE startup
occurs once for several compilation cycles, something as (pseudocode)

main() {
    DO_GUILE_START_UP();
    do {
        COMPILE_FILES()
        PROMPT("PRESS 'E' TO END, 'R' TO RECOMPILE THE SAME FILE/S")
    } while (GETCHAR()=='R');
    exit(0);
}