I noticed whenever I want to delete a folder containing a lot of data using a command line (sudo rm -r folder_name), the Terminal hangs on for the operation to terminate. But at the same time, when I manually delete a folder of similar size, the deletion is performed instantly without waiting.
Any explanation as to why this difference happens
This updates the pointers to the files. Yes, or to be more accurate it updates directory's listing of inodes which actually are the pointers to blocks of disk space we call files. +1ed. Also if there's just minimal number of subdirectories and majority of files are there, that's gonna be faster probably, since I think it's only necessary to move subdirectory's inode to another directory's listing. Removing is recursive traversal of whole directory - that's opening syscalls, unlinking syscalls, etc, so of course longer. – Sergiy Kolodyazhnyy Oct 23 '18 at 21:26