Balancer

The balancer is a kernel feature that allows to get more performances out of most important applications.

• How the balancer works
• Application processes suspension
• Performance mode

How the balancer works

The balancer allows to manage the priority of userland processes - and only them. Here is the list of its features:

• Increase priority of this application: gives a priority of 8 to the process linked to the active window ;
• Give maximum priority to this application: gives a priority of 10 to the process linked to the active window ;
• Set this application with maximum priority: always give a priority of 8 to this application's processes ;
• Suspend/resume this application: see below ;
• Enter performance mode: see below

Application processes suspension

Application processes can be suspended, which is an equivalent of pause where they don't run at all. This is achieved by setting their priority to 0.

A suspended application can then be resumed, and because it was just suspended it will instantly run again, without any data loss.

When a process is suspended, all its child processes are, too.

Performance mode

The performance mode performs the following actions:

• For all userland processes with a non-null priority, set their priority to 1 ;
• For all the processes of the application related to the active window, set a priority of 10.

This makes all other applications running a lot slower, but the current one will run a lot faster. The priority is re-calculated whenever the active window changes.

When a fullscreen application uses more than 50% of CPU in fullscreen, or when it asks for it, an overlay suggesting to enter performance mode is shown.

Performance mode is automatically exited when the related process exits.