Unikernel-Based Real-Time Virtualization Under Deferrable Servers: Analysis and Realization

Authors Kuan-Hsun Chen , Mario Günzel , Boguslaw Jablkowski, Markus Buschhoff, Jian-Jia Chen

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Author Details

Kuan-Hsun Chen
  • University of Twente, The Netherlands
Mario Günzel
  • TU Dortmund University, Germany
Boguslaw Jablkowski
  • EMVICORE GmbH, Dortmund, Germany
Markus Buschhoff
  • EMVICORE GmbH, Dortmund, Germany
Jian-Jia Chen
  • TU Dortmund University, Germany

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Kuan-Hsun Chen, Mario Günzel, Boguslaw Jablkowski, Markus Buschhoff, and Jian-Jia Chen. Unikernel-Based Real-Time Virtualization Under Deferrable Servers: Analysis and Realization. In 34th Euromicro Conference on Real-Time Systems (ECRTS 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 231, pp. 6:1-6:22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


For cyber-physical systems, real-time virtualization optimizes the hardware utilization by consolidating multiple systems into the same platform, while satisfying the timing constraints of their real-time tasks. This paper considers virtualization based on unikernels, i.e., single address space kernels usually constructed by using library operating systems. Each unikernel is a guest operating system in the virtualization and hosts a single real-time task. We consider deferrable servers in the virtualization platform to schedule the unikernel-based guest operating systems and analyze the worst-case response time of a sporadic real-time task under such a virtualization architecture. Throughout synthesized tasksets, we empirically show that our analysis outperforms the restated analysis derived from the state-of-the-art, which is based on Real-Time Calculus. Furthermore, we provide insights on implementation-specific issues and offer evidence that the proposed scheduling architecture can be effectively implemented on top of the Xen hypervisor while incurring acceptable overhead.

Subject Classification

ACM Subject Classification
  • Computer systems organization → Embedded and cyber-physical systems
  • Software and its engineering → Real-time systems software
  • Unikernel
  • Virtualization
  • Reservation Servers
  • Deferrable Servers
  • Cyber-Physical Systems
  • Real-Time Systems


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