In this post I show how you can use MeterListener to listen to Instrument measurements, how to trigger Observable measurements, and how to aggregate values.

Andrew Lock's blog focuses on ASP.NET Core development, web APIs, and software architecture. Readers can find tutorials, code samples, and explanations covering topics such as RESTful API design, authentication, and authorization in ASP.NET Core. Additionally, they can learn about dependency injection, middleware, and performance optimization techniques.

.NET Escapades

A deep dive into using `MeterListener` from the `System.Diagnostics.Metrics` APIs to consume and aggregate metrics in-process within a .NET application. The post walks through building a `MetricManager` wrapper class that subscribes to specific ASP.NET Core and .NET runtime instruments, handles both standard and observable instrument types, and aggregates measurements using thread-safe primitives like `Interlocked`. A live-updating console table powered by Spectre.Console displays the collected metrics. Key concepts covered include selecting which instruments to listen to, triggering observable instruments via `RecordObservableInstruments()`, handling different measurement types with typed callbacks, and the performance rationale behind the API design.

Recording metrics in-process using MeterListener

Creating a service to display the results