[racket] big-bang is slow to render on screen?

This probably isn't a help, but just in case...

Also check the xorg conf file and syslog for which driver it's using (it 
often autodetects nowadays, and picks from among applicable installed 
drivers).

In addition to which driver it's picking up, also check for whether it 
was able to load any device firmware blob or secondary (closed source) 
shared library.

(Incidentally, I've actually noticed better 2D behavior overall from the 
open-source driver for my old Radeon laptop, except for video scaling.)

Also maybe restart the xorg server or reboot.  I don't know give that 
advice, and I don't know the xorg internals, but occasionally (esp. with 
closed driver) I have noticed performance behavior that seems like the 
server might be bogged down with cached pixmaps or similar.  I've seen 
this with Firefox.

Neil V.