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Gem5-X: A Many-core Heterogeneous Simulation Platform for Architectural Exploration and Optimization

Authors:

Yasir Mahmood Qureshi,

William Andrew Simon,

Marina Zapater,

Katzalin Olcoz,

David AtienzaAuthors Info & Claims

ACM Transactions on Architecture and Code Optimization (TACO), Volume 18, Issue 4

Article No.: 44, Pages 1 - 27

https://doi.org/10.1145/3461662

Published: 17 July 2021 Publication History

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Abstract

The increasing adoption of smart systems in our daily life has led to the development of new applications with varying performance and energy constraints, and suitable computing architectures need to be developed for these new applications. In this article, we present gem5-X, a system-level simulation framework, based on gem-5, for architectural exploration of heterogeneous many-core systems. To demonstrate the capabilities of gem5-X, real-time video analytics is used as a case-study. It is composed of two kernels, namely, video encoding and image classification using convolutional neural networks (CNNs). First, we explore through gem5-X the benefits of latest 3D high bandwidth memory (HBM2) in different architectural configurations. Then, using a two-step exploration methodology, we develop a new optimized clustered-heterogeneous architecture with HBM2 in gem5-X for video analytics application. In this proposed clustered-heterogeneous architecture, ARMv8 in-order cluster with in-cache computing engine executes the video encoding kernel, giving 20% performance and 54% energy benefits compared to baseline ARM in-order and Out-of-Order systems, respectively. Furthermore, thanks to gem5-X, we conclude that ARM Out-of-Order clusters with HBM2 are the best choice to run visual recognition using CNNs, as they outperform DDR4-based system by up to 30% both in terms of performance and energy savings.

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Index Terms

Gem5-X: A Many-core Heterogeneous Simulation Platform for Architectural Exploration and Optimization
1. Computer systems organization
  1. Architectures
    1. Other architectures
      1. Heterogeneous (hybrid) systems
2. Hardware
  1. Emerging technologies
    1. Analysis and design of emerging devices and systems
      1. Emerging architectures
      2. Emerging simulation

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cover image ACM Transactions on Architecture and Code Optimization

ACM Transactions on Architecture and Code Optimization Volume 18, Issue 4

December 2021

497 pages

ISSN:1544-3566

EISSN:1544-3973

DOI:10.1145/3476575

Editor:
David Kaeli
Northeastern University, USA

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Publication History

Published: 17 July 2021

Accepted: 01 April 2021

Revised: 01 March 2021

Received: 01 August 2020

Published in TACO Volume 18, Issue 4

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EU FEDER and the Spanish MINECO
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https://doi.org/10.3390/mi15050557
Åleskog CGrahn HBorg A(2024)A Comparative Study on Simulation Frameworks for AI Accelerator Evaluation2024 IEEE International Parallel and Distributed Processing Symposium Workshops (IPDPSW)10.1109/IPDPSW63119.2024.00073(321-328)Online publication date: 27-May-2024
https://doi.org/10.1109/IPDPSW63119.2024.00073
Yue SLiang H(2024)Anlu NP: The Abstract Level Modeling of Network Processor for Agile Hardware Design2024 5th International Conference on Computer Engineering and Application (ICCEA)10.1109/ICCEA62105.2024.10603556(266-272)Online publication date: 12-Apr-2024
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Niemier MHu XLiu LSharifi MO’Connor IAtienza DAnsaloni GLi CKhan ARalph D(2023)Cross Layer Design for the Predictive Assessment of Technology-Enabled Architectures2023 Design, Automation & Test in Europe Conference & Exhibition (DATE)10.23919/DATE56975.2023.10136923(1-10)Online publication date: Apr-2023
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Gu C(2023)A study on impacts of hardware changes on performance of different multithreading libraries based on Gem5Journal of Physics: Conference Series10.1088/1742-6596/2646/1/0120262646:1(012026)Online publication date: 1-Dec-2023
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