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Performance test your ASP.NET Core app using Bombardier

In the past I’ve always used Apache Bench, Fiddler or Visual Studio Load Testing to test the performance of my ASP.NET (Core) applications and API's. Recently I made the switch to Bombardier, a versatile HTTP benchmarking tool written in Go.

 If you have Go Go installed on your system, you can install Bombardier using the following command:

go get -u github.com/codesenberg/bombardier

But you can also download a binary compatible to your OS directly from the releases without the need to install Go.

I already started my ASP.NET Core application:

Running the tool is quite easy. Invoke the bombardier command with the target URL and some extra parameters:

bombardier -c 100 -n 1000 –l http://localhost:5042/WeatherForecast

This command will send 1000 requests with 100 concurrent connections to your application.

Bombardier will provide detailed statistics:

  • Reqs/sec: Requests per second.
  • Latency: Average response time.
  • Latency Distribution: Percentiles (50%, 75%, 90%, 95%, 99%) of response times.

You can customize Bombardier by adjusting parameters like concurrency, duration, and headers. Next step is to integrate Bombardier into our CI/CD pipeline or use it at scale with tools like Crank, but that is something I’ll leave for another post.

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