It would be nice if Dophin copies files with a higher I/O niceness than 0. May be the default should be 6 or 7? It would also be nice if the user can configure this and change it on running copy operations. I would like to have this feature because when I copy big files, other programs stutter. When I change the io-niceness then in Konsole, they work much better.
All of Dolphin's file operations are handled by KIO; moving this there.
And actually, a duplicate of Bug 383415. *** This bug has been marked as a duplicate of bug 383415 ***