Abstract
The OpenMP accelerator model enables an efficient method of offloading computation from host CPU cores to accelerator devices. However, it leaves it up to the programmer to try and utilize CPU cores while offloading computation to an accelerator. In this paper, we propose HetroOMP, an extension of the OpenMP accelerator model that supports a new clause hetro which enables computation to execute simultaneously across both host and accelerator devices using standard tasking and work-sharing pragmas.
To illustrate our proposal for a hybrid execution model, we implemented a proof-of-concept work-stealing HetroOMP runtime for the heterogeneous TI Keystone-II MPSoC. This MPSoC has host ARM CPU cores alongside accelerator Digital Signal Processor (DSP) cores. We present the design and implementation of the HetroOMP runtime and use several well-known benchmarks to demonstrate that HetroOMP achieves a geometric mean speedup of 3.6\(\times \) compared to merely using the OpenMP accelerator model.
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Acknowledgments
We are grateful to the anonymous reviewers for their suggestions on improving the presentation of the paper, and to Eric Stotzer from Texas Instruments for shipping a brand new TI Keystone-II MPSoC to IIIT Delhi.
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Kumar, V., Tiwari, A., Mitra, G. (2019). HetroOMP: OpenMP for Hybrid Load Balancing Across Heterogeneous Processors. In: Fan, X., de Supinski, B., Sinnen, O., Giacaman, N. (eds) OpenMP: Conquering the Full Hardware Spectrum. IWOMP 2019. Lecture Notes in Computer Science(), vol 11718. Springer, Cham. https://doi.org/10.1007/978-3-030-28596-8_5
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