https://bugs.freedesktop.org/show_bug.cgi?id=109331
--- Comment #6 from andrew.m.mcmahon@gmail.com --- One last comment before I leave it to the experts.
Another bug report with Unity 18.04: https://steamcommunity.com/app/10500/discussions/0/3441214221460524307/
If anyone wants to go above and beyond the call of duty then I've uploaded some traces for Medieval 2 here: https://drive.google.com/open?id=17LUb2EsS3oqYjEyZ-yxIB_C_DBnS0Wz8
I've used the same trick of disabling/enabling PBO surfaces.
Finally what exactly are PBO surfaces? Do I need them? What's the penalty for not using them? The game seems to trace faster with them off than on. Are the Linux ports by Feral a bit wonky and/or prone to strange behaviour - or are they generally decent?