Hand-Over-Hand Transactions with Precise Memory Reclamation

In this paper, we introduce revocable reservations, a transactional memory mechanism to reserve locations in one transaction and check whether they are unchanged in a subsequent transaction without preventing reserved locations from being reclaimed in the interim. We describe several implementations of revocable reservations, and show how to use revocable reservations to implement lists and trees with a transactional analog to hand-over-hand locking. Our evaluation of these data structures shows that revocable reservations allow precise and immediate reclamation within transactional data structures, without sacrificing scalability or introducing excessive latency.