Evaluating contention management using discrete event simulation

Understanding the behavior and benefits of contention managers is important for designing transactional memory implementations. Contention manager design is closely tied to other design deci-sions in a transaction memory implementation, and therefore ex-periments to compare the behaviors of contention managers are difficult. This paper presents a discrete event simulator that allows researchers to explore the behavior of contention managers and even to perform experiments that compare lazy conflict detection without contention management to eager detection combined with a contention manager. For our benchmarks, lazy conflict detection is competitive with the best contention managers even if the con-tention manager can be implemented with no runtime overheads. Our experiments confirm that contention management design is critical for transactional memories that use eager validation. 1