Note that "lock-free" doesn't mean "doesn't use mutexes"; it means "at least one consumer/producer will always make progress". (Any algorithm using locks fails

Note that "lock-free" doesn't mean "doesn't use mutexes"; it means "at least one consumer/producer will always make progress". (Any algorithm using locks fails this test, as one stubborn consumer/producer can hold up the entire system.) The article doesn't seem to really touch on this property at all (although at first glance the algorithm does appear to be lock-free).