One of the nice features introduced in Android 4.2 Jelly Bean on tablet devices is the ability to create user accounts just like you do on desktop operating systems. However, as far as I can see, there doesn't seem to be a log-off option available anywhere that would result in e.g. stopping all processes initiated by a user.
The only standard option in the multi-user environments world I can see is switching between user accounts. In order to do that, all I need to do on my Google Nexus 7 tablet is lock the screen and then unlock it by hitting the hardware on/off button; on the screen that shows up you can select what user account you'd like to log in to.
This is quite important as I am worried the processes started by other users might have an impact on the performance of the device.