benchmark #

benchmark provides a standard way of writing and running benchmarks in Dart. Inspired by both benchmark_harness and test.

Writing Benchmarks. #

Benchmarks are specified using the top-level benchmark() function:

import 'package:benchmark/benchmark.dart';

void main() {
  benchmark('List.generate(100k)', () {
    List.generate(100000, (i) => i);
  });
}

Benchmarks can be grouped together using the group() function. Each group's description is added to the beginning of its benchmark's descriptions:

import 'package:benchmark/benchmark.dart';

void main() {
  group('List', () {
    benchmark('.generate(100k)', () {
      List.generate(100000, (i) => i);
    });
  });

  group('Map', () {
    benchmark('.unmodifiable(other)', () {
      Map.unmodifiable({
        'value': 1
      });
    }, iterations: 100);
  });
}

You can use the setUp() and tearDown() functions to share code between benchmarks. The setUp() callback will run before every benchmark in a group, and tearDown() will run after:

import 'package:benchmark/benchmark.dart';

void main() {
  List<int> list;
  setUp(() {
    list = List.generate(100000, (i) => i);
  });

  tearDown(() {
    list = null;
  });

  benchmark('List(100k).forEach()', () {
    list.forEach(() {});
  });
}

You can use the setUpEach() and tearDownEach() functions to share code between iterations of benchmarks. The setUpEach() callback will run before every iteration in a benchmark, and tearDownEach() will run after:

import 'package:benchmark/benchmark.dart';

void main() {
  List<int> list;
  setUpEach(() {
    list = List.generate(100000, (i) => i);
  });

  tearDownEach(() {
    list = null;
  });

  benchmark('List(100k).map()', () {
    list.map((i) => '$i');
  });
}

Running benchmarks #

benchmark comes with a simple executable to automatically run all your benchmarks:

dart pub run benchmark

See the --help flag for more information.