Intelligent Data Storage

As parallel computer architectures significantly shrinking the execution time in compute kernels, the performance bottlenecks of applications shift to the rest of part of execution, including data movement, object deserialization/serialization as well as other software overheads in managing data storage. To address this new bottleneck, the best approach is to not move data and endow storage devices with new roles.

Morpheus is one of the very first research project that implements this concept in real systems. We utilize existing, commercially available hardware components to build the Morpheus-SSD. The Morpheus model not only speeds up a set of heterogeneous computing applications by 1.32x, but also allows these applications to better utilize emerging data transfer methods that can send data directly to the GPU via peer-to-peer to further achieve 1.39x speedup. Summarizer further provides mechanisms to dynamically adjust the workload between the host and intelligent SSDs, making more efficient use of all computing units in a system and boost the performance of big data analytics. This line of research also helps Hung-Wei's team receive Facebook research award, 2018.

• Facebook research award, 2018
• Hung-Wei Tseng, Qianchen Zhao, Yuxiao Zhou, Mark Gahagan and Steven Swanson. Morpheus: Exploring the Potential of Near-Data Processing for Creating Application Objects in Heterogeneous Computing. SIGOPS Operating Systems Review, volume 51(2):71 -- 83, August 2018.
• Gunjae Koo, Kiran Kumar Matam, Te I, Hema Venkata Krishna Giri Narra, Jing Li, Steven Swanson, Murali Annavaram, and Hung-Wei Tseng. Summarizer: Trading Bandwidth with Computing Near Storage. In 50th Annual IEEE/ACM International Symposium on Microarchitecture, MICRO 2017
• Yanqin Jin, Hung-Wei Tseng, Steven Swanson and Yannis Papakonstantinou. KAML: A Flexible, High-Performance Key-Value SSD. In 23rd International Symposium on High Performance Computer Architecture (HPCA 2017). February 2017.
• Hung-Wei Tseng, Qianchen Zhao, Yuxiao Zhao, Mark Gahagan and Steven Swanson. Morpheus: Creating Application Objects Efficiently for Heterogeneous Computing. In 43rd International Symposium on Computer Architecture (ISCA 2016). June 2016.

Building Efficient Heterogeneous Computers

As the discontinuation of Dannard scaling and Moore's Law, computers become heterogeneous. However, moving data among heterogeneous computing units and storage devices becomes an emerging bottleneck in these systems.

My research proposes the "Hippogriff" system that revisits the programming model of moving data in heterogeneous computer systems. Instead of using the conventional CPU-centric, programmer-specified methods, the Hippogriff system simplifies the application interface and provide a middle layer to efficiently handle the data movement. We also implemented peer-to-peer data transfer between the GPU and the SSD in the Hippogriff system.

The preliminary result demonstrates 46% performance gain by applying Hippogriff to a set of rodinia GPU applications. For highly optimized GPU MapReduce framework, Hippogriff still demonstrates up to 27% performance gain.

• Jing Li, Hung-Wei Tseng, Chunbin Lin, Steven Swanson, and Yannis Papakonstantinou. HippogriffDB: Balancing I/O and GPU Bandwidth in Big Data Analytics. Proceedings of VLDB Endowment, Volume 9(14), 2016.
• Yang Liu, Hung-Wei Tseng, Mark Gahagan, Jing Li, Yanqin Jin and Steven Swanson. Hippogriff: Efficiently Moving Data in Heterogeneous Computing Systems. In 34th IEEE International Conference on Computer Design (ICCD 2016). Oct. 2016.
• Yang Liu, Hung-Wei Tseng and Steven Swanson. SPMario: Scale Up MapReduce with I/O-Oriented Scheduling for the GPU. In 34th IEEE International Conference on Computer Design (ICCD 2016). Oct. 2016.
• Hung-Wei Tseng, Yang Liu, Mark Gahagan, Jing Li, Yanqin Jin, and Steven Swanson. Gullfoss: Accelerating and Simplifying Data Movement among Heterogeneous Computing and Storage Resources . Department of Computer Science and Engineering, University of California, San Diego technical report technical report CS2015-1015, 2015.

Machine Learning Assisted Data Storage

The advancement of machine learning techniques enables more accurate predictions, data classifications and lead to improved decision making. This is especially helpful for dealing with system design issues that traditionally rely on heuristics. In this project, we use machine learning models to replace traditional heuristic-based mechanisms to better assist the management of storage systems. The initial result shows 19% extension in SSD lifetime without adding any hardware cost.

• Te I, Murtuza Lokhandwala, Yu-Ching Hu, and Hung-Wei Tseng. Pensieve: a Machine Learning Assisted SSD Layer for Extending the Lifetime. In IEEE International Conference on Computer Design (ICCD 2018). October, 2018.
• Te I, Yu-Ching Hu, Murtuza Taher Lokhandwala, and Hung-Wei Tseng. Extending SSD Lifetime with Machine Learning. The 9th Non-Volatile Memories Workshop, NVMW 2018, 2018.