Software: I have written production software for systems such as high-performance messaging libraries, Web search infrastructure (particularly index serving and load-balancing servers), and the original article similarity service for Google Scholar. I have worked on the design of software systems for cluster-level tracing, profiling storage availability and power management, among others.
Hardware: I have worked on several aspects of Google's hardware infrastructure such as the design of energy-efficient servers, high-availability datacenter infrastructure, storage systems, and the design of hardware accelerators for machine learning. While at Digital Equipment (later Compaq) I was one of the architects of Piranha, an influential multi-core shared memory multiprocessor design.
Leadership: I am a VP of Engineering managing the Geo Platform team, the group responsible for the data and imagery that powers products such as Google Maps, Local Search and Google Earth, among others. I have been a manager and technical lead of the team that builds Google's computing platform, from facility power distribution and cooling infrastructure to the design of servers, storage and networking equipment. I have co-authored the first book on the design of we have come to call Warehouse-scale computers -- a term that describes the massive computing systems that run today's planetary-scale cloud services. It remains the primary reference text in this emerging field.