Microservices AntiPatterns and Pitfalls

Chapter 9. Are We There Yet Pitfall

With the microservices architecture every service is deployed as a separate application, meaning all of the communication to a microservice from the client or API layer, as well as communication between services, requires a remote call.

This pitfall occurs when you don’t know how long the remote access call takes. You might assume the latency it around 50 milliseconds, but have you ever measured it? Do you know what the average latency is for your particular environment? Do you know what the “long tail” latency is (e.g., 95, 99, 99.5 percentiles) for your environment? Measuring both of these metrics is important, because even with good average latency, bad long-tail latency can destroy you.

Measuring Latency

Measuring the remote access latency under load in your production environment (or production-like environment) is critical for understanding the performance profile of your application. For example, let’s say a particular business request requires the coordination of four microservices. Assuming that your remote access latency is 100 milliseconds, that particular business request would consume 500 milliseconds just in remote access latency alone (the initial request plus four remote calls between services). That is a half a second of request time without one single line of source code being executed for the actual business request processing. Most applications simply cannot absorb that sort of latency.

You might think the way to avoid ...