The idea behind the RadTextSlot is to be lighter, to consist only of a TextBlock and a Background, nothing more. Still it will be loading on scrolling and zooming, but since it will be lighter, it should not take as much resources. However, this should be implemented in our code, not in your application.
The best that you could achieve at the moment is to follow the recommendations from the article:
In some cases when using a big number of special slots there could be some performance
issues in the RadScheduleView control. In order to not lose performance when using Special and ReadOnly slots you should keep in mind the following measures:
Populate the Slots that are in the visible range only.
If a Slot is in multiple Resources at the same time do not create a separate Slot for each Resource but rather assign the Resources to the Slot.
If a Slot is recurring do not create many different separate Slots but rather create a recurring one.
Treat the Slots as Appointments, the same performance principals exist.
Hope this clears out the manner.
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