This simple tutorial will explain how to restart unity and unity-2d in Ubuntu. Normally we need to restart unity only when meet a “no response” problem. If restarting unity can’t fix your issue, maybe you need to try restart your X display manager.
Restart unity without reset compiz
You can press ALT+F2, then type “unity” in Run a command box and then click ENTER to restart unity.
Or you can run below command in terminal(Ctrl+ALT+T) to restart unity:
Restart unity by restarting compiz
Execute this command in terminal:
setsid compiz --replace
Restart Unity 2D:
Run below commands in your terminal to restart unity 2D:
pkill unity-2d-shell pkill unity-2d-panel
Restart X display Manager
If above methods can’t fix your issue,you may need to try restart your X display manager.
Note:All opened applications will lost
sudo -s setsid service lightdm restart