Is anyone also experiencing rather slow front end behaviour in Mathematica 11.0.1 on Linux (Deb 8.7 + kde)? I am experiencing quite slower saving times of notebooks themselves and slower response times of GUI (compared to the same version on the same machine under windows 7). Sometimes after having Mathematica open for longer time (~hrs), the gui freezes completely.
The resolution is to periodically completely close mathematica and start again as soon as the gui responsivness becomes slower.