02-14-2020, 11:03 PM
How much memory is it when you reload? 58GB for a 20Mpix image is quite a lot, when I load an image from my 20Mpx camera the image is 750M (converted to 32-bit FP...). And after copying/pasting layers, i get up to 3.6GB, flattening the image take me up to 4.8GB, but deleting the undo history bring the image back to the initial 750MB. When you image is bigger than the tile cache size Gimp starts swapping to disk and this can slow down things tremendously.