recovery files deleted by rm with Extundelete for ext4

I deleted some very important files by using rm command.

I refer the tutoral http://abloz.com/2013/09/12/linux-rm-rf-file-recovery-record.html

But at the last step, the command should be –recovery-directory

But it will NOT work if we do not unmount the disk. So finally, it did not work.

PS, the command to check the disk of a directory is

dh -Th directory_path