I'd be happy to explain the JavaScript benchmark on MeasureThat.net.

Overview

The benchmark tests three approaches for introducing delays in asynchronous code: await delayA, delayT (a wrapper around setTimeout), and setTimeout directly.

Options Compared

1. await delayA: This approach uses a custom promise-based delay function, delayA. It returns a promise that resolves after the specified time.
2. delayT: This is a modified version of setTimeout, which wraps its arguments in an array and applies them to a new function with the original timeout value. The main difference is that it uses apply() instead of passing arguments directly, as shown in the benchmark code.
3. setTimeout: A direct call to the native setTimeout function.

Pros and Cons

• await delayA:
  • Pros: This approach is idiomatic for JavaScript promises, making it easy to read and understand. It also avoids the need to use setTimeout directly.
  • Cons: The custom promise-based delay function may incur overhead compared to native setTimeout.
• delayT:
  • Pros: This implementation preserves the original arguments passed to setTimeout, which can be useful in certain scenarios. It's also a simple and straightforward approach.
  • Cons: Using apply() might incur additional overhead, making it slightly slower than await delayA or native setTimeout.
• setTimeout:
  • Pros: This is the most efficient option, as it leverages the native JavaScript engine for scheduling tasks. It's also the most straightforward approach.
  • Cons: This approach can be less readable due to its direct call to a native function.

Library and Special JS Features

The test uses no external libraries or special JavaScript features (such as Web Workers or async/await polyfills). The custom delayA function is used only within the benchmark code, not in any production environment.

Other Alternatives

Some alternative approaches for introducing delays could include:

• Using Promise.then() instead of promises or native setTimeout.
• Implementing a timer using Node.js's setImmediate() function.
• Utilizing Web Workers to schedule tasks asynchronously.