Heterogeneous Intra-Pipeline Device-Parallel Aggregations

The rising hardware heterogeneity in modern systems emphasizes new dimensions of optimizing task execution for data processing frameworks. Specialized hardware is often expected to be the exclusive executor of some particular workload because it was designed for it or is simply the fastest option. In heterogeneous database systems, almost always, the entire operation offloading is considered. However, little attention was given to database systems with horizontal cross-device pipeline parallelization. We argue that such an approach can be applied to systems with morsel-driven parallelism and improve performance. We apply our parallelization strategy to an existing system and accelerate aggregations using two devices by up to 1.5x compared to the fastest exclusive device executor.