It's advantageous for the process of trying a passphrase to be too slow to do a million times a second but fast enough that it isn't bothersome to the user. Thi

It's advantageous for the process of trying a passphrase to be too slow to do a million times a second but fast enough that it isn't bothersome to the user. This is a tunable parameter --iter-time given in ms when adding or modifying a passphrase to a slot. If I understand correctly its cryptsetup luksChangeKey DEVICE --iter-time <time in ms> Consult your manual and backup before making any changes to encrypted devices lest tragedy ensue. 2 things of note. - Luks slots are tried in succession adding a second faster slot after a slow slot will be slower because it will try the slow one first fail then unlock with the fast slot. - You should back up your luks header because a small amount of corruption in the right place can make the entire encrypted volume unrecoverable