Await Benchrmark

await_benchmark.dart

import "dart:async";

const NeverInline = "NeverInline";

Future<double> measureForSync(void fun()) async {
  int c = 0;
  int e = 0;
  final sw = Stopwatch()..start();
  do {
    fun();
    e = sw.elapsedMilliseconds;
    c++;
  } while (e < 2000);
  return c/e;
}

Future<double> measureForAsync(FutureOr fun()) async {
  int c = 0;
  int e = 0;
  final sw = Stopwatch()..start();
  do {
    await fun();
    e = sw.elapsedMilliseconds;
    c++;
  } while (e < 2000);
  return c/e;
}

@NeverInline
int fooSync() => 0;

@NeverInline
FutureOr<int> fooFutureOr() => 0;

@NeverInline
Future<int> fooFuture() => Future.value(0);

@NeverInline
Future<int> fooAsync() async => 0;

main() async {
  for (var i = 0; i < 5; i++) {
    var d = 0.0;
    d = await measureForSync(fooSync);
    print("fooSync, No await: $d /ms");
    await new Future(()=>0);
    
    d = await measureForAsync(fooSync);
    print("fooSync, awaited: $d /ms");
    await new Future(()=>0);
    
    d = await measureForSync(fooFutureOr);
    print("fooFutureOr, No await: $d /ms");
    await new Future(()=>0);
    
    d = await measureForAsync(fooFutureOr);
    print("fooFutureOr, awaited: $d /ms");
    await new Future(()=>0);
    
    d = await measureForSync(fooFuture);
    print("fooFuture, No await: $d /ms");
    await new Future(()=>0);
    
    d = await measureForAsync(fooFuture);
    print("fooFuture, awaited: $d /ms");
    await new Future(()=>0);

    d = await measureForSync(fooAsync);
    print("fooAsync, No await: $d /ms");
    await new Future(()=>0);
    
    d = await measureForAsync(fooAsync);
    print("fooAsync, awaited: $d /ms");
    await new Future(()=>0);
  }
}