Distributed computing using feedback control in the data center

Professor Sanjay Lall at ECE Fall 2025 Colloquium

The bittide system is a recent approach to distributed computing, designed to achieve synchronous execution at a large scale without the need for a global clock or traditional wall-clock synchronization. It aims to overcome the complexity and expense of maintaining precise wall-clock time in distributed systems, especially at datacenter scale. The underlying mechanism of bittide uses feedback control to regulate the frequency of the hardware oscillators driving both computation and communication, in such a way as to ensure that all nodes operate in syntony. This allows applications to treat time as purely logical, and to make use of deterministic scheduling and programming methodologies across the entire datacenter.  In this talk we present an overview of the bittide system, discussing how the system works, mathematical formulations of the system behavior, and the consequences of logical synchrony for applications.