PiMulator: a Fast and Flexible Processing-in-Memory Emulation Platform (DATE 2022)
PiMulator talk at DATE 2022
Sergiu Mosanu, Mohammad Nazmus Sakib, Tommy Tracy II, Ersin Cukurtas, Alif Ahmed, Preslav Ivanov, Samira Khan, Kevin Skadron, Mircea Stan
University of Virginia School of Engineering and Applied Science
Motivated by the memory wall problem, researchers propose many new Processing-in-Memory (PiM) architectures to bring computation closer to data. However, evaluating the performance of these emerging architectures involves using a myriad of tools, including circuit simulators, behavioral RTL or software simulation models, hardware approximations, etc. It is challenging to mimic both software and hardware aspects of a PiM architecture using the currently available tools with high performance and fidelity. Until and unless actual products that include PiM become available, the next best thing is to emulate various hardware PiM solutions on FPGA fabric and boards. This paper presents a modular, parameterizable, FPGA synthesizable soft PiM model suitable for prototyping and rapid evaluation of Processing-in-Memory architectures.
The PiM model is implemented in System Verilog and allows users to generate any desired memory configuration on the FPGA fabric with complete control over the structure and distribution of the PiM logic units. Moreover, the model is compatible with the LiteX framework, which provides a high degree of usability and compatibility with the FPGA and RISC-V ecosystem. Thus, the framework enables architects to easily prototype, emulate and evaluate a wide range of emerging PiM architectures and designs.
We demonstrate strategies to model several pioneering bitwise-PiM architectures and provide detailed benchmark performance results that demonstrate the platform's ability to facilitate design space exploration. We observe an emulation vs. simulation weighted-average speedup of 28x when running a memory benchmark workload. The model can utilize 100% BRAM and only 1% FF and LUT of an Alveo U280 FPGA board. The project is entirely open-source.
PiMulator is available at: https://github.com/hplp/PiMulator
ResearchGate page: https://www.researchgate.net/publicat...
FPGA Emulation, Fidelity, Simulation Wall, Processing-in-Memory (PiM), High-Bandwidth Memory (HBM)
We would like to thank Ameen Akel and Sean Eilert from Micron Technology for their valuable and helpful input. This work was supported in part by Semiconductor Research Corporation (SRC), and in part by the NSF I/UCRC on Multi-functional Integrated System Technology (MIST) Center; IIP-1439644, IIP-1439680, IIP-1738752, IIP-1939009, IIP-1939050, and IIP-1939012.