The team at Brown University, led by Prof. Rodrigo Fonseca, has done a lot of research in the space of distributed tracing, including the development of event-based tracing system X-Trace [1], monitoring framework Pivot Tracing [2], which we will discuss in this chapter, and many other projects. They have developed the Tracing Plane [3], a shared set of components that provide core generic metadata propagation (or "baggage", which is where the term came from) on top of which the other projects are built. Recently, the Tracing Plane has been generalized in a more principled way [4] that we are going to review here.
The need for a general-purpose context propagation framework becomes obvious if we consider a large number of existing so-called "cross-cutting" tools that focus on the analysis and management of end-to-end executions in distributed systems, such as using tenant IDs for resource accounting and coordinated scheduling decisions across components; propagating targeting...