Architecture, Abstraction and Application: Three A’s that keep Zhou at the top of her class

Brown’s newest Assistant Professor of Engineering Peipei Zhou bridges the gap between computer science and engineering, seamlessly flowing between the physical hardware/operating system, the abstraction/optimization interface, and the software output.

Still settling into her sparsely decorated office on the third floor of the Engineering Research Center, and patiently awaiting the outfitting of a laboratory, Peipei Zhou has already immersed herself into Brown Engineering’s collaborative culture. A quick look at her biography says she is an Assistant Professor of Engineering and director of the Customized Computer Architecture Research Lab, but a few minutes spent with her tells you her reach is far beyond what one would associate with a young faculty member. 

Customized computer architecture is the buzzword phrase for Zhou’s work. Her most recent endeavor involves a chiplet system for autonomous cars and includes collaboration with researchers from Wayne State University and the University of Delaware. “Potentially, we can do much better computing with lower latency on autonomous driving,” she explains. “Because in an autonomous driving vehicle, as you know, the latency constraint is very strict, like a millisecond. One millisecond is a very strict deadline. If that deadline is missed, it could have a very catastrophic result.”

That is just one of the customized applications Zhou feels passionately about. She also has ongoing collaborations for projects involving precision medicine and semiconductor devices, and points to the open letter signed by 13 women university presidents and deans of engineering from six institutions (Brown’s Christina Paxson and Tejal Desai among them) in support of the CHIPS and Science Act as one of the top reasons she landed on College Hill.

Zhou received her bachelor’s degree in electrical and computer engineering from Southeast University, Chien-Shiung Wu Honor College in 2012, a master’s in electrical and computer engineering from the University of California, Los Angeles in 2014, and a Ph.D. in computer science from UCLA in 2019. It was at UCLA where she studied with Computer Science Professor Jason Cong, an academic giant in Field-Programmable Gate Array (FPGA), and electronic design automation technology. 

Her undergraduate work allowed her to choose her major in what Zhou says was strikingly similar to the way Brown’s Open Curriculum works. “We could personalize a course plan after sophomore year and that is when I made the decision that I wanted to focus on the hardware and software interface, and then how to build and program new computing systems.” The further training and continuation for the next seven years as a Ph.D. student in computer science was spent building more expertise and exposure to real-world applications, she said. 

“At that time, we worked on human genome processing and medical imaging applications. We built computing infrastructure that increased the computing process of sequencing the whole human genome from about two days down to 30 minutes, which has since been deployed in UCLA’s Institute for Precision Health.

“Those are the things I want to be able to do. That was my Ph.D. thesis,” she said. More broadly, her thesis investigated modeling and optimization for customized computing at chip-level, node-level, and cluster-level, using the acceleration of the widely used Genome Analysis Toolkit by focusing on its algorithm and hardware co-design as one example. 

“If we can apply this technique in the data center scale, which now consumes upwards of three percent of the global power consumption, then even a small percentage savings is huge in terms of carbon cost.”

“I really feel like (customizing computer architecture) is good for many different domains,” she said. “When we build a chip, or chip design, we want to make it work so it can be applied to, and benefit others, on a large scale.

“In 2014, I joined Microsoft Research as a summer intern, and at that time, Microsoft was working on a new project with chips in the data center. I found out later that the code was deployed in thousands of computing machines in the Microsoft data center. So, whenever you use Bing search, that’s it. That’s when I started to realize, this is something that can benefit everyone’s life. The impact is not really that noticeable because users are just using the services – whatever the computing improvements, energy is saved, and that makes a real life impact.

“If we can apply this technique in the data center scale, which now consumes upwards of three percent of the global power consumption, then even a small percentage savings is huge in terms of carbon cost.”

Zhou’s group has also begun to work on managing or reusing and rebuilding chips, coining it REFRESH (Revisiting Expanding FPGA Real-estate for Environmentally Sustainability Heterogeneous-Systems) to create new chiplets. “It means that we keep these chips and we can put them to use for another 10 years, instead of just disposing of them.”

Open source documentation is also a critical component of her work, which helps in building community. “I’m often asked are you a computer scientist or electrical engineer because you have all those devices? Well, we sit as an interface to this computing device hardware and also the program or the software. We open source every software and hardware that we have – how we design and program the chip is a very fundamental research question we ask ourselves and then when we solve that, we open source the software stack.”

Teaching ENGN2911X Reconfigurable Computing in the fall has given her the opportunity to connect with graduate-level Brown students while aiding the transfer of the rising doctoral candidates in her lab over from the University of Pittsburgh. She looks forward to welcoming undergrads into her ENGN1600 Design and Implementation of Digital Integrated Circuits in the spring, while continuing to grow her lab and getting to know those around her – fellow faculty, students and staff, who she says have been so welcoming thus far. 

“It’s about how to build things, but it starts with the people.”