Hi David, On Mon, Jul 08, 2024 at 10:21:09PM +0200, David Hildenbrand wrote: > BTW, I was just trying to understand how MADV_FREE + MAP_DROPPABLE would > behave without any swap space around. > > Did you experiment with that? You mean on a system without any swap configured? That's actually my primary test environment for this. It behaves as expected: when ram fills up and the scanner is trying to reclaim what it can, folio_test_swapbacked(folio) is false, and the memory gets freed. After, reads fault in a zero page. So it's working as expected. Jason