App on Linux - really slow... any ideas why?

[Ken Ray]

I've got a basic PC (Dell Dimension 4600 running a P4 at 2.66GHz with 2GB
RAM) that switch boots between Windows XP and Ubuntu 8.04.  I have a pretty
complex app (my stick figure animaton program "Stykz") that loads about 8
libraries has  a few front and back scripts and when it opens it displays a
main window and 4 floating palettes.

The app is built with the Rev 3.5 engine and when I launch it on Windows, it
takes about 5 seconds from initial launch to idle. When I do this on Ubuntu
it is agonizingly slow, taking 25-30 seconds to come to an idle state. And
after this, everything is like molasses - windows take seconds! to redraw,
mouse messages aren't recognized immediately, etc.

I haven't done much on Linux except StackRunner, which was very lightweight,
but my overall question is: are there any "gotchas" I should know about
related to Linux that might account for significantly affecting performance?

TIA,

Ken Ray
Sons of Thunder Software, Inc.
Email: kray at sonsothunder.com
Web Site: http://www.sonsothunder.com/