Re: an interesting test of gnumeric

[Miguel de Icaza <miguel nuclecu unam mx>]

> Now you have a big fibbionacci spreadsheet with lots of recursive
> addition on it.  Set the bottom right selector thingie to average.
> Now start selecting a single cell and dragging your collection to cover
> a large rectangle.  The expansion of the selection region is very
> slow for me.

Yes.  The problem is not with the computation engine, but with the
code redraw engine in the canvas.

My guess is that I am invalidating the whole region instead of the
changes (this is just a theory though, I believe I invalidate the
proper spots in the cell marking code) and this might be causing the
slowness.

This first appeared on the Dec 15 hacking that Fedeico did to the
canvas, I am not sure what might be causing this.

> 1) Perhaps these values could be cached rather then being recomputed
> on the fly;

They are not recomputed at all unless you change a cell.

> He glanced at gnumeric for about 5 seconds and said "I'm
> installing GNOME."  Keep up the great work!

I am glad to hear that.  I will look into this problem, it might very
well be my rectangle-invalidate code.

Miguel.