Thesis defense: Josh Fried

Thesis Title: Next Generation Operating Systems for the Datacenter

Presenter: Josh Fried

Presenter’s Affiliation: CSAIL

Thesis Supervisor: Adam Belay

Date: April 1, 2025

Time: 3PM

Location: 32-G882 (Hewlett)

Abstract: Modern datacenters must handle an ever-growing array of real-time and data-intensive workloads—such as interactive web services and AI models—that demand both low latency and high throughput. However, traditional operating systems introduce significant I/O overhead, degrading performance and limiting efficiency. A common workaround is to let applications communicate directly with hardware, bypassing the OS entirely. While this improves performance, it sacrifices compatibility with existing software and requires dedicating hardware to each application, ultimately reducing overall resource utilization.

This thesis proposes a new datacenter OS architecture built around three systems—Shenango, Caladan, and Junction—that deliver high I/O performance without these trade-offs. First, Shenango enables applications to bypass traditional OS-mediated I/O without dedicating CPU cores solely to polling. Next, Caladan ensures that idle resources can be used productively by other applications by actively managing competition for microarchitectural resources, thereby preserving each application’s high I/O performance and responsiveness. Finally, Junction overcomes several common limitations of kernel-bypass solutions, bringing these benefits to all applications by preserving compatibility with existing software stacks and reducing memory and polling overheads.

Collectively, these systems provide the advantages of direct hardware access without sacrificing the flexibility or efficiency of a general-purpose operating system. This work demonstrates that high I/O performance, efficient resource utilization, and broad application compatibility can indeed coexist, paving the way for a new generation of datacenter operating systems.

Details

• Date: Tuesday, April 1
• Time: 3:00 pm - 4:00 pm
• Category: Thesis Defense
• Location: 32-G882 (Hewlett Room)