The adoption of serverless functions is reaching record levels within enterprise organizations. Interestingly, given the growing adoption and interest, many monitoring solutions silo performance of the code executed in these environments, or provide just basic metrics about the execution. To understand the performance of applications, I want to know what bottlenecks exist, where time is being spent, and the current state of each system involved in fulfilling a request. While metrics, logs, and segmented stack traces are helpful, a more cohesive performance story is still the most useful way to understand an application, and should be achievable using existing technologies.
In this post, I’ll explore how to achieve a cohesive performance story using OpenTracing to instrument an Express app running in a local container, and a function running on Lambda. For visualizations and analysis, I’ll use LightStep [x]PM for this example, although you can choose another OpenTracing backend like Jaeger.