Coding Bolt

Performance measurement is essential in modern software development. For years, .NET developers have been familiar with the Stopwatch class to measure execution time. But in .NET 7, a new method has been added: Stopwatch.GetElapsedTime(). Let’s explore this new approach that has zero memory allocations.

Traditional Approach:

Before diving into the new method, let’s first recap the traditional approach. Traditionally, measuring elapsed time would look something like this:

Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();

// Do something...

stopwatch.Stop();
TimeSpan elapsedTime = stopwatch.Elapsed;

While simple and effective, there is a hidden cost: memory allocation. Every time we create a new Stopwatch instance, we’re allocating memory. For most applications, this is negligible. But for performance-critical applications or areas of code that get executed frequently, these allocations can add up.

The New Approach:

long startTime = Stopwatch.GetTimestamp();

// Do something...

TimeSpan elapsedTime = Stopwatch.GetElapsedTime(startTime);

With this new approach:

1. Zero Memory Allocations: Since we are not creating a new Stopwatch instance, there are zero memory allocations, making it ideal for performance-critical paths.
2. Simple and Clear: The code remains clear about its intent—getting the elapsed time.

Conclusion:

While the traditional Stopwatch approach will still be suitable for many scenarios, the new Stopwatch.GetElapsedTime method is a welcome addition for those looking to minimize memory allocations, especially in performance-critical paths. As developers, it’s always beneficial to have more tools in our arsenal, and this method is a testament to .NET’s commitment to performance optimization.