Exploring Parallelism on Flutter: Main Thread, Isolate and Compute.

• Main Thread: We all know Dart (Flutter) code runs in a single thread, which is a main thread aka main isolate. This thread is responsible for painting UI, handling user interaction and responding to the user interactions. Below you can see an example where I am fetching data on the main thread, that might overload the main thread and lead to sluggish performance and unresponsive UI, causing a jarring experience for users.

• Isolate: Dart introduces Isolate to achieve true parallelism. Isolate has its own memory space that allow to perform computation without blocking the main thread. Communication between isolates is done using ports: ‘SendPort’ and ‘ReceivePort’. Below is an example of isolate where I am fetching data using isolate without hampering the main thread. 

• Compute: Just above we read about isolate now what is ‘compute’? Isolate provides parallelism, but, manually handling them could be a tedious task, so Dart has provided us a compute method which provides parallelism without having to create ports like in the isolates. Below is an example of a compute method from which I am fetching data. 

Performance: 

I tested all three ways to fetch the data and here’s the result. Isolate is faster than others. 

Choosing the Right Tool for the Job:

• Main thread: Stick to UI updates, animations, and user interactions.
• Isolates: Use for computationally intensive tasks, network requests, and background processing.
• Compute: Ideal for short-lived, simple calculations. And when you don't want to configure Isolates 🤣

Things to remember:

• Communication: Isolates require message passing for communication, while compute doesn't.
• Complexity: Isolates offer more control but require more setup, while compute is simpler but less flexible.
• Memory: Isolates have separate memory spaces, while compute shares the main thread's memory.

Conclusion:

Understanding the nuances of main thread, isolates, and compute empowers you to make informed decisions about concurrency in your Flutter projects. By leveraging these tools strategically, you can ensure a smooth, responsive, and performant user experience, taking your Flutter apps to the next level!

Bonus Tip: Experiment with different approaches and measure performance to find the optimal solution for your specific use case.

I hope this article provides a clear and concise explanation of these concurrency concepts in Flutter. Feel free to ask if you have any further questions or need more specific examples!. Please do share your feedback and comments below! Your insights contribute to a vibrant community of Flutter developers.

For More:

https://docs.flutter.dev/perf/isolates

https://docs.flutter.dev/cookbook/networking/background-parsing