Introducing Speculative Optimizations in Task Dataflow with Language Extensions and Runtime Support

Abstract—We argue that speculation leads to increased parallelism in the coarse-grain dataflow paradigm. To do so, we present a framework for adding speculation in a popular and well-established framework. We specify a limited set of additions to the OmpSs language and changes required in its supporting runtime environment. These modifications enable speculation across the system in a flexible way. We evaluate our implementation using a simple benchmark leading to a promising 10 % speedup. I