Named a 2022 Intel Rising Star Faculty Awardee, Xu Credits Colleagues for an Expanding Research Horizon in Computing

Just a few years ago, when Illinois Computer Science professor Tianyin Xu joined the department, he came with a thorough level of expertise in making computer systems reliable and secure. His research experience was connecting this expertise to cloud and datacenter systems, by detecting and fixing software bugs, configuration errors, and system design flaws.

Up to that point, Xu had not foreseen turning that expertise into a fruitful collaboration with colleagues focused on hardware and operating system kernels, but that is exactly what his experience at Illinois CS provided – an opportunity to disrupt the status quo, think outside the box, and grow in surprising ways.

Through a connection with his faculty mentor, Illinois CS professor Josep Torrellas, and his former PhD student Dimitrios Skarlatos (who recently joined Carnegie Melon University), a unique partnership did form.

The collaboration made strides in many different ways, including the recently funded Center on Transformative Server Architectures, outstanding PhD thesis award, award-winning papers, and practical impacts. The most recent of which being Xu’s selection as a 2022 Intel Rising Star Faculty Award recipient.

“The credit really should go to my students and collaborators. I would have never pursued these topics without Josep and Dimitrios, and I would not have reached nearly as far without everyone’s influence,” Xu said. “I never imagined that I would be recognized by a leading hardware company like Intel. It’s a great honor.”

A rare distinction, the Intel Rising Star Faculty Award acknowledged just 15 early career faculty members in 2022. These individuals presented “impressive works in computer science, electrical engineering, computer engineering, material science, and chemical engineering.”

Xu’s inclusion focused on his work recognizing, first, that “security is a pressing concern for cloud and datacenter computing, and (Xu) has centered his recent work on operating system (OS) security.”

That, Xu said, stemmed from a 2020 paper – entitled “Draco: Architectural and Operating System Support for System Call Security” – that he co-authored with Skarlatos, Torrellas, and two of Xu’s graduate students. The project continued, as the team “upstreamed their work on operating system (OS) security to the Linux kernel.” The effort was led by Xu’s former undergraduate student, YiFei Zhu (now a kernel engineer at Google) with collaborators from IBM and RedHat.

Xu has continued working on the research direction, which is now led by CS PhD student Jinghao Jia who recently presented the work at the Linux Plumber Conference last month.

Thinking back to his first year as a junior faculty at Illinois CS, when the journey began, Xu remembers that he mostly worked on his own, without student yet. It was through Torrellas’ guidance, and the excitement of their projects with Skarlatos, that Xu found a new niche and began developing it.

“I went outside of my comfort zone to grow,” Xu said. “Prior to working with Josep, I didn’t really expand my research boundaries. In fact, I was super worried in the beginning, because I found that I learned much more than I contributed. Josep and Dimitrios are always incredibly kind and patient to teach me, which really encouraged me. I then found that the problems were really important and fun to work on.”

The collaboration also led to the second line of work that Intel acknowledged through the Rising Star award, regarding virtual memory systems.

The award summary states: “Over the next five years, his project aims at making the virtual memory subsystem easy to customize and extend to accommodate the emerging needs. Xu also plans to design new virtualization technologies at the layers of OS and cluster management systems to effectively and securely support heterogenous and hybrid cloud.”

Xu said that this line of work began with the team’s computer architecture innovations – with papers published at ASPLOS 2020 and ASPLOS 2022 – led by Skarlatos previously and CS PhD student Jovan Stojkovic.

“We are incredibly proud of our architectural design of virtual memory, which resulted in a series of top-tier conference papers. We started taking it to hardware vendors like Intel and AMD, seeking practical impacts and possible adoption,” Xu said. “The most common response is: ‘Wow, the design great, but how can the OS kernel support it?’ So, we decided to show the feasibility by building the kernel ourselves. This requires a disruptive redesign of the current virtual memory system implementation.”

Together with CS PhD student Siyuan Chai and MS student Jiyuan Zhang, the team has been working on building a versatile virtual memory system on top of the Linux kernel that can efficiently support different architectural designs including the existing x86 design and the new design from the team.

“It’s a very ambitious and challenging project,” Xu said. “The Linux kernel implementation is hardcoded to the x86 design; making it versatile needs drastic design and implementation changes. The nature of the research requires us to change both the hardware and the software.”

Thinking in terms of what the next five years offer, as the Intel Rising Stars Award indicated, Xu is thrilled to look ahead and not just reflect upon previous accomplishments.

He’s excited about an opportunity to continue shaping the research into something useful and impactful.

And that’s what he looks forward to the most; a continued connection with his colleagues and students, built on the promise of producing something that can change computing for the better.

“The best part of this research is that I feel as excited as when I started here at Illinois CS,” Xu said. “I cannot be more grateful to my students who are so courageous to work on those ambitious projects and are very independent to enable me to explore new topics, as well as my collaborators who are always kind, supportive and helpful.”