Re: Parallelizing Lilypond [was: Re: Sibelius Software UK office shuts down]

[David Kastrup]

Joseph Rushton Wakeling <address@hidden> writes:

> So what do you think about the potential of an algorithm going something like 
> this:
>
>     (1) Read in enough bars of music to take up a little over 2 pages [you can
>         presumably do a rough estimate of the width and height of bars and 
> staff
>         systems on the fly].
>
>     (2) Engrave that music.  Keep the first page written.
>
>     (3) If the music is completely engraved, keep the second page as well, and
>         stop.  Otherwise, rewind to the start of the second page and return
>         to step (1), reading and engraving from this new start point.
>
> So basically you're doing: engrave pp. 1 & 2, keep page 1; engrave
> pp. 2 & 3, keep page 2; engrave pp. 3 & 4, keep page 3; ....
>
> You could generalize this to engraving N+1 pages (N >= 1) at a time
> and keeping the first N pages written.
>
> That should keep a firm cap on calculation size and memory
> consumption, as you'd only ever be engraving N+1 pages at a time.  It
> would probably be slower for small scores, but would make it possible
> to build scores of any size with a constant memory footprint.

I think we have enough real problems without inventing artificial
challenges.

-- 
David Kastrup