NuGet.Benchmarks

A micro-benchmark project based on BenchmarkDotNet for quick performance experiments inside the NuGet.Client repository.

Purpose

This project exists to make it easy to write and run micro-benchmarks against NuGet source code without having to set up a separate repository or solution. It is intended for local use only — benchmark class files are git-ignored by the .gitignore in this folder, so you can create them freely without worrying about accidentally committing them.

Use it for:

Profiling allocations and throughput while developing a feature or fix.
Comparing the performance of two implementation approaches before committing.
Reproducing a performance regression reported in an issue.

How to run

dotnet run -c Release --project test/TestExtensions/NuGet.Benchmarks/NuGet.Benchmarks.csproj

Note: Always run benchmarks in Release configuration. Debug / unoptimised builds produce misleading results.

Writing benchmarks

Program.cs auto-discovers all classes that implement IBenchmark in the assembly — you never need to edit it.

Create a new *.cs file in this directory (it will be automatically git-ignored).
Add a public class that implements IBenchmark.
Annotate the methods you want to measure with [Benchmark].
Run the project in Release mode (see above).

Example

// MyBenchmarks.cs  (git-ignored, safe to create locally)
using BenchmarkDotNet.Attributes;

[MemoryDiagnoser]
public class LambdaAllocationBenchmarks : IBenchmark
{
    [Benchmark]
    public void StaticLambda()
    {
        Create(static path => new Item(path));
    }

    [Benchmark]
    public void Lambda()
    {
        string pre = "my prefix";
        Create(path => new Item(path + pre));
    }

    private static void Create<T>(Func<string, T> factory) { }
}

public class Item
{
    public Item(string value) => Value = value;
    public string Value { get; }
}

For full documentation on available attributes ([MemoryDiagnoser], [Params], [GlobalSetup], etc.) see the BenchmarkDotNet docs.