I'm using Lubuntu 11.10 x86-64, Nvidia binary driver v304, Snes9x 1.53 GTK+ port version 82.
When the sync to vertical blank option is not enabled, Snes9x uses 100% CPU time when emulation is paused, or when e.g. the preferences or Open ROM Image window is open. Also there's a significant difference in CPU usage in-game when sync to vertical blank is off vs on: on ~17%, off ~30%.
100% CPU usage when paused on Snes9x Linux GTK+ port v.82
Re: 100% CPU usage when paused on Snes9x Linux GTK+ port v.8
Replying to my own post... It turns out that bug has been fixed in the latest git version.