VHPC 2025 Program

For detailed timing and schedule information, please refer to the schedule page.

Tutorial

Writing a hypervisor from scratch

Presenter: Seiya Nuta
Affiliation: Vercel Inc.

This tutorial provides hands-on experience in hypervisor development, covering fundamental concepts and practical implementation techniques for building virtualization infrastructure from the ground up.

Abstract: Hardware-assisted virtualization technologies like Intel VT and AMD SVM have long been viewed solely as mechanisms for running virtual machines. This talk challenges the preconception - it's actually a hardware-assisted try-catch mechanism, where the hypervisor effectively behaves as a "catch" block for VM exits. Through this metaphor, we will revisit virtualization from scratch, explore recent virtualization-based applications, rethink what hardware-assisted virtualization is, and brainstorm what we could invent in the near future.

Accepted Paper Presentations

Enabling RDMA and GPUs in Rootless Kubernetes for Accelerated HPC and AI Applications

Authors:
  • • Lise Jolicoeur - University of Bordeaux & CEA, France
  • • François DiakhatĂ© - CEA DAM Ile de France, France
  • • Daniel J Milroy - Lawrence Livermore National Laboratory, USA
  • • Vanessa Sochat - Lawrence Livermore National Laboratory, USA

Abstract: HPC workflows increasingly integrate diverse technologies such as artificial intelligence (AI), machine learning (ML), data analytics, databases, and web services. Orchestrators like Kubernetes have been designed to facilitate deploying these heterogeneous workloads in cloud environments. Allowing Kubernetes to be launched and managed as a resource on HPC clusters would facilitate the deployment of modern workflows in HPC environments. To enable the deployment of Kubernetes by unprivileged HPC users, we evaluate the usability of a rootless version of Kubernetes, Usernetes. We analyze synthetic benchmarks as well as HPC and ML proxy apps to evaluate the overhead of Usernetes for HPC/ML workloads deployed on high performance networks and GPUs. While the results show that applications running in Usernetes can take advantage of InfiniBand networks and NVIDIA GPUs, some benchmarks incur measurable overheads at scale which warrant further investigation.

Performance Analysis of Container-in-VM Architectures: A Study on Hypervisor Isolation and Lightweight OS Integration

Authors:
  • • Vijayalakshmi Saravanan - University of Texas at Tyler & BNL, USA
  • • Khaled Z Ibrahim - Lawrence Berkeley National Laboratory, USA
  • • Manoj Kumar Patra - The LNMIIT, Jaipur & National Institute of Technology, Rourkela, India

Abstract: Container-in-VM architectures have become essential in modern cloud-native infrastructure, offering a secure yet flexible approach to deploying containerized workloads. This paper comprehensively reviews the architectural and performance trade-offs associated with deploying containers inside virtual machines, focusing on hypervisor-level isolation and lightweight operating system integration. We systematically examine a decade of research and industry innovations, synthesizing findings from benchmarking studies and architectural implementations. The paper introduces a comparative framework covering isolation strength, runtime overhead, boot latency, OS footprint, and orchestration compatibility, highlighting how solutions like Firecracker, Kata Containers, and unikernels deliver varying balances of efficiency and security. A significant contribution is the analytical contrast between general-purpose and minimalistic operating systems when used as VM guests, revealing substantial gains in performance and attack surface reduction with specialized OS choices. Similarly, hypervisor technologies are evaluated in terms of their ability to support microVMs and fast container lifecycle management, with observations drawn from real-world deployments and empirical studies. The findings demonstrate that combining lightweight OS stacks with hardware-assisted virtualization can significantly enhance container performance, though challenges persist in orchestration, observability, and standardization. This review identifies critical gaps and offers direction for future research in building secure, efficient, and scalable container-in-VM platforms suitable for cloud, edge, and serverless environments.

WebAssembly and Unikernels: A Comparative Study for Serverless at the Edge

Authors:
  • • Valerio Besozzi - University of Pisa, Italy
  • • Enrico Fiasco - University of Pisa, Italy
  • • Marco Danelutto - University of Pisa, Italy
  • • Patrizio Dazzi - University of Pisa, Italy

Abstract: Serverless computing at the edge requires lightweight execution environments to minimize cold start latency, especially in Urgent Edge Computing (UEC). This paper compares WebAssembly and unikernel-based MicroVMs for serverless workloads. We present Limes, a WebAssembly runtime built on Wasmtime, and evaluate it against the Firecracker-based environment used in Spare. Results show that WebAssembly offers lower cold start times for lightweight functions but struggles with complex workloads, while Firecracker provides higher but more stable cold start times and better execution performance, particularly for I/O-heavy tasks.

Research Areas Covered

Hypervisor Development

  • • From-scratch hypervisor implementation
  • • Virtualization infrastructure fundamentals
  • • Hands-on development techniques

HPC & AI Integration

  • • RDMA networking in containerized environments
  • • GPU acceleration for AI workloads
  • • Rootless Kubernetes deployment

Container & VM Architecture

  • • Container-in-VM performance analysis
  • • Hypervisor isolation vs. performance
  • • Lightweight OS integration strategies

Edge Computing Technologies

  • • WebAssembly for edge serverless
  • • Unikernel deployment strategies
  • • Resource-constrained environment optimization

Workshop Format

Tutorial Session

50-minute hands-on tutorial on hypervisor development

Research Papers

3 technical papers covering virtualization, containers, and edge computing

Duration

3 hours of technical content with coffee break

General Information

The 20th Workshop on Virtualization in High-Performance Cloud Computing (VHPC 2025) will be held in conjunction with the International European Conference on Parallel and Distributed Computing (Euro-Par 2025), on Aug 26, 2025, in Dresden, Germany.

For more information, refer to either the VHPC 2025 homepage or the Euro-Par 2025 web pages.