While using the disk manipulator to import a ton of essence from a 16384k storage drive to external storage drawers, the tps dropped to less than 9 from 20 instantly. It goes back to 20 immediately after removing the disk. Using exporters to the drawers even several at a time did not create tps lag. I am playing on the Oceanblock modpack single player. I didn't have anyway to load up a refined storage storage disk to see if it was a rs issue.