Change Autofill settings in iTunes on PC

In the iTunes app on your PC, use Autofill settings to add songs in a certain order, set how much reserved space is required, and more.

Option				Description
Replace all items when Autofilling				Replace all songs every time you use Autofill.
Choose items randomly				Sync a random list of songs to your device.
Choose higher rated items more often				Add items with higher ratings more often than those with lower ratings. This option is only available when you select “Choose items randomly.”
Reserve space for disk use				Set aside disk capacity space to use as a hard disk.

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iTunes User Guide