Resident task settings Scanner (Basic) and Scanner (Advanced) Risk vs Performanc

-1 but just to add what is the point of stateful when they update every half hour. You loose more then you gain and in any case for the loss you might as well have every thing scanned on access.

Yes it is but Persistent will mean in avast one you select it all safe files (or for that matter files you select) will not be scanned again ever.