I have used gparted quite a few times just to create new partitions on empty drives but on a few occasions I have started to use gparted to shrink an exiting partition to allow me enough space to create a new partition in the unused space of the disk - specifically this time I wanted to shrink an existing partition down to about 3.3TB and use the unused space of about 3.8TB for the new partition. I made the mistake again of thinking that shrinking a partition should be quick . . more than a day later gparted was still “moving blocks” . .
I don’t understand this - why is it necessary to move ANY blocks . . I can see that if I was moving 3.3TB from one place on the drive to another new or overlapping place that that would need to take some time - but why does shrinking and making available UNUSED space take so much time?