In recent software transactional memory proposals, a contention manager module is responsible for ensuring that the system as a whole makes progress. A number of contention manager algorithms have been proposed and empirically evaluated. In this paper we lay some foundations for a theory of contention management. We present the greedy contention manager, the first to combine non-trivial provable properties with good practical performance. In a model where transaction delays are finite, the greedy manager guarantees that every transaction commits within a bounded time, and the time to complete n concurrent transactions that share s objects is within a factor of s(s + 1)/2 of the time that would have been taken by an optimal offline list scheduler. No contention manager reviewed in the literature satisfies both the properties. Benchmark results convey our claim of the practicality of the greedy manager.
Guerraoui et al. REF provided the first theoretical analysis of contention managers, showing that the Greedy contention manager is O(s 2 ) competitive relative to an optimal offline scheduler, where s is the number of shared data items.
Toward a theory of transactional contention managers
PODC '05
Computer Science