The CAOS group at CMU bridges computer architecture and operating systems
and rethinks their synergy for performance, security, and scalability

Computing systems are undergoing a radical shift, propelled by stern security requirements and an unprecedented growth in data and users. This change has proven to be abstraction breaking. Current hardware and operating system abstractions and interfaces were built at a time when we had minimal security threats, scarce compute and memory resources, and limited numbers of users. These assumptions are not representative of today's computing landscape. On one hand, modern virtualization technologies have enabled the new cloud paradigms of serverless computing and microservices, which have in turn lead to the sharing of computing resources among hundreds of users. On the other hand, attacks such as Spectre and Meltdown have shown that current hardware is plagued by critical vulnerabilities. In this new era of computing, it is urgent that we rethink the synergy between the OS and hardware layers from scratch. Our research at CAOS bridges computer architecture and operating systems focusing on performance, security, and scalability. Our current work follows two central themes: (a) re-designing abstractions and interfaces between the two layers to improve performance and scalability, and (b) uncovering security vulnerabilities and building defenses at the boundary between hardware and OS.

• 2025

  Initial patches of Contiguitas have been upstreamed into Linux 6.15!

  Learn more about the patches.

• 2025

  Joshua was selected for the Allen Newell Award for Excellence in Undergraduate Research!

  The Allen Newell Award for Excellence in Undergraduate Research is presented annually to the best honor thesis in the School of Computer Science at CMU and it recognizes undergraduate research that exemplifies the scientific process, rigorous analysis, and deep impact.

• 2025

  Dimitrios received the Amazon Research Faculty Award!

  Learn more about the award.

• 2025

  Dimitrios received the Wilton E. Scott Institute for Energy Innovation Faculty Award!

  Learn more about the award.

• 2025

  EMT accepted at OSDI 2025!

  Learn more about our work on an OS framework for new nemory translation architectures.

• 2025

  Joshua was selected for the CRA Outstanding Undergraduate Research Honorable Mention!

  The CRA Undergraduate Research Awards (“URA”) program recognizes undergraduate students in North American colleges and universities who show outstanding potential in an area of computing research.

• 2024

  Cinnamon accepted at ASPLOS 2025!

  Learn more about our work on a framework for scale-out encrypted AI.

• 2024

  Dimitrios received the Intel Rising Star Faculty Award!

  Learn more about the award.

• 2024

  Dimitrios received the Linux and eBPF Foundation Faculty Award!

  Learn more about the award.

• 2024

  Eliot and Vasilis join the CAOS group!

  Welcome!

• 2024

  Kaiyang and Hilbert (Yuang) win the Qualcomm Innovation Fellowship 2024!

  • Learn more about the Qualcomm Innovation Fellowship.
  • CMU School of Computer Science news.

• 2024

  Perspective accepted at ISCA 2024!

  •Learn more about our work on a principled framework for secure speculation in operating systems.
  • CMU CyLab news.

• 2024

  Contiguitas selected as an IEEE MICRO Top Picks!

  Learn more about our work on the pursuit of physical memory contiguity in datacenters.

• 2024

  David Rudo was selected for the CRA Outstanding Undergraduate Research Honorable Mention!

  The CRA Undergraduate Research Awards (“URA”) program recognizes undergraduate students in North American colleges and universities who show outstanding potential in an area of computing research.

• 2023

  Hilbert joins the CAOS group!

  Welcome!

• 2023

  Memento accepted at MICRO 2023!

  Learn more about our work on ephemeral memory management in serverless environments.

• 2023

  Two papers, Siloz, and XFaaS, accepted at SOSP 2023!

  Learn more about our work on:
  • DRAM isolation.
  • Hyperscale and frugal Function-as-a-Service.

• 2023

  Contiguitas won the best paper ISCA 2023!

  •Learn more about our work on the pursuit of physical memory contiguity in datacenters.
  •CMU School of Computer Science news.

• 2023

  Contiguitas accepted at ISCA 2023!

  Learn more about our work on the pursuit of physical memory contiguity in datacenters.

• 2023

  ServiceRouter accepted at OSDI 2023!

  Learn more about our work on a minimal service mesh for datacenters.

• 2023

  Dimitrios received the NSF CAREER Award!

  Learn more about our work on rebuilding virtual memory across hardware and operating systems.

• 2023

  IOCost selected as an IEEE MICRO Top Picks!

  Learn more about our work on block IO control for containers in datacenters.

• 2022

  Memory Efficent Hashed Page Tables accepted at HPCA 2023!

  Learn more about our work on Memory Efficient Hashed Page Tables.

• 2022

  Siddharth and Patrick join the CAOS group!

  Welcome!

• 2022

  Dimitrios received three Meta research awards to improve datacenter computing systems!

  Learn more about the awards:
  • Meta Security Research Award.
  • Meta Systems Research Award.
  • Meta AI Hardware/Software Codesing.
  • CMU School of Computer Science news.

• 2022

  TMO won the best paper award at ASPLOS 2022!

  Learn more about our work on transparent memory offloading in datacenters.

• 2022

  Three papers, IOCost, TMO, and Nested ECPTs, accepted at ASPLOS 2022!

  Learn more about our work on:
  • Block IO control for containers in datacenters.
  • Transparent memory offloading in datacenters.
  • Parallel virtualized memory translation.

• 2021

  Dimitrios selected as a Meta Academic of the Month!

  Read the article.

• 2021

  Dimitrios received a Meta Faculty Award!

  For his work on architectural and operating system support for lightweight virtualization.

• 2021

  Dimitrios received the David J. Kuck Outstanding Ph.D. Thesis Award!

  Awarded to a single outstanding doctoral thesis from the computer science department at UIUC each year.

• 2021

  RAS accepted at SOSP 2021!

  Learn more about our work on continuously optimized region-wide datacenter resource allocation.

• 2021

  Dimitrios received the ACM SIGARCH & IEEE CS TCCA Outstanding Dissertation Award!

  For "contributions to redesigning the abstractions and interfaces that connect hardware and operating systems".

• 2021

  NVOverlay accepted at ISCA 2021!

  Learn more about our work on efficient and scalable high-frequency snapshotting to NVM.

• 2021

  Kaiyang and Ziqi join the CAOS group!

  Welcome!

• 2021

  BabelFish selected as an IEEE MICRO Top Picks!

  Learn more about our work on fusing address translations for containers.

• 2021

  Elastic Cuckoo Page Tables selected as a a MICRO Top Picks Honarable Mention!

  Learn more about our work on rethinking virtual memory translation for parallelism.

• 2021

  The upstreamed Draco is featured in Linux Security at Phoronix!

  Learn more about the upstreamed Draco.

• 2021

  Jamais Vu accepted at ASPLOS 2021!

  Learn more about our work on thwarting microarchitectural replay attacks.

• 2021

  Draco has been upstreamed in the Linux Kernel!

  Learn more about our work on architectural and operating system support for system call security.

• 2021

  CAOS Group Established!

  And so it begins...