Getting a deadlock occasionally when several threads trying to access [PFUser currentUser] when using parse iOS sdk v1.2.20
It looks like whenever I make a PFQuery call or PFCloud function call, these operations also access [PFUser currentUser], so there's increase chance of deadlock if you are making queries from separate threads.
Anyone else find a solution for this, I doubt parse even is aware of the problem as they closed these related issues long ago: https://www.parse.com/questions/parse-locking-up-the-main-thread-possible-deadlock And this one: https://www.parse.com/questions/occasional-freezing-at-pfuser-currentuser
Parse has released an update with a possible fix of the currentUser deadlock.
Hopefully this fixes your situation.
Check the changelog and try updating to Parse SDK v1.7.2.
来源：https://stackoverflow.com/questions/25419611/access-to-pfuser-currentuser-causing-deadlock