java slower in rawhide?

[Bruno Wolff III]

After upgrading from F9 to rawhide, a java game, Colossus, I play a lot
is running annoyingly slow. Is there something that changed between F9
and rawhide that would account for this? Colossus won't work with gcj,
so I don't have the option to switch to that java to see if it's faster.
glxgears still runs with about the same frame rate it did previously, so
I don't think it is a graphics driver slow down.