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Isolate Example
A sample application that demonstrate best practices when using isolates.
Goals
- Display the performance benefits of isolates when using them in the right situation.
- Show how to use the
computemethod for straightforward computations. - Demonstrate how to initialize and use an isolate.
- Show the cost of moving data between isolates and provide alternatives.
The important bits
performance_page.dart
Compares running a large computation on the main isolate with running the same calculation
on a second isolate. When the main isolate is used, Flutter is unable to render new frames, and
the SmoothAnimationWidget's animation freezes.
infinite_process_page.dart
Creates an isolate used to run an infinite loop that sums batches of 100M randomly generated numbers at a time. Users can start, terminate, pause, and resume the isolate, as well as modify how the calculation is performed.
data_transfer_page.dart
Demonstrates how expensive it is to move large amounts of data between isolates and a better alternative to move data. This page creates an isolate that can add up a list of numbers and gives users three options for how to provide it with input:
- Send values normally using a List
- Send the values using TransferableTypedData
- Generate the values on the second isolate, so no copying is necessary
Users can then compare the performance of each approach using the displayed timestamps.
Questions/issues
If you have a general question about any of the techniques you see in the sample, the best places to go are:
If you run into an issue with the sample itself, please file an issue in the main Flutter repo.