Can Transactions Enhance Parallel Programs?

Transactional programming constructs have been proposed as key elements of advanced parallel programming models. Currently, it is not well understood to what extent such constructs enable efficient parallel program implementations and ease parallel programming beyond what is possible with existing techniques. To help answer these questions, we investigate the technology underlying transactions and compare it to existing parallelization techniques. We also consider the most important parallelizing transformation techniques and look for opportunities to further improve them through transactional constructs or – vice versa – to improve transactions with these transformations. Finally, we evaluate the use of transactions in the SPEC OMP benchmarks