UICollectionView performance - _updateVisibleCellsNow

Question

I\'m working on a custom UICollectionViewLayout that displays cells organized by day/week/month.

It is not scrolling smooth, and it looks like the lag i

Answer 1

Also don't forget to try to rasterize the layer of the cell:

cell.layer.shouldRasterize = YES;
cell.layer.rasterizationScale = [UIScreen mainScreen].scale;

I had 10 fps without that, and boom 55fps with! I'm not really familiar with GPU and compositing model, so what does it do exactly is not entirely clear to me, but basically it flatten the rendering of all subviews in only one bitmap (instead of one bitmap per subview?). Anyway I don't know if it has some cons, but it is dramatically faster!