CDS&E: Collaborative Research: HyLoC: Objective-driven Adaptive Hybrid Lossy Compression Framework for Extreme-Scale Scientific Applications

Today's extreme-scale scientific simulations and instruments are producing huge amounts of data that cannot be transmitted or stored effectively. Lossy compression, a data compression approach leading to certain data distortion, has been considered as a promising solution, because it can significantly reduce the data size while maintaining high data fidelity. However, the existing lossy compression methods may not always work effectively on all datasets used in specific applications because of their distinct and diverse characteristics. Moreover, the user objectives in compression quality and performance may vary with applications, datasets or circumstances. This project aims to develop a hybrid lossy compression framework to automatically construct the best-fit compression for diverse user objectives in data-intensive scientific research. Educational and engagement activities are provided to develop new curriculum related to scientific data compression and promote research collaborations with national laboratories. Designing an efficient, adaptive, hybrid framework that can always choose the best-fit compression strategy is nontrivial, since existing state-of-the-art lossy compression methods are developed with distinct principles. The project has a three-stage research plan. First, the project decouples the state-of-the-art error-bounded lossy compression approaches into multiple stages and effectively models the working efficiency (e.g., compression ratio, error, speed) of particular approaches in each stage. Second, the project develops a loosely-coupled framework to aggregate the decoupled compression stages together and also explores as many compression pipelines composed of different stages as possible, to optimize the classic compression efficiency, including compression quality and performance. Third, the project optimizes the synthetic data-movement performance regarding the external devices and resources, such as I/O performance. The team evaluates the proposed framework on multiple extreme-scale scientific applications, including cosmological simulations, light source instrument data analytics, quantum circuit simulations, and climate simulations. The project may create technologies that can increase the storage availability and improve the performance for extreme-scale scientific applications, opening opportunities for new discoveries. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.