Is this with the Dart VM or dartj2s (or both?)

This comment was originally written by nbily...@gmail.com

Just the Dart VM

Removed Type-Defect label.
Added Type-Enhancement, Area-VM, Triaged labels.

Added Performance label.

Could you please provide a small Dart program that exhibits the slow performance. Thanks.

This comment was originally written by nbilyk...@gmail.com

I've attached a benchmark harness.

I'm running
Dart VM version: 0.8.10.3_r29803 (Mon Nov 04 09:52:29 2013) on "windows_ia32"

In the Dart VM method closures all have the same hashCode, and are very slow within Maps. When using dart2js and running the same code through JavaScript, the hashCodes are different and performance is good.

With 1000 references there was a 200x performance difference.

Attachment:
dartscratchpad.dart (1.20 KB)

This comment was originally written by @tatumizer

same with reflection:
showHashCodeCollision() {
  var f1=(a,b)=>10;
  var f2=()=>15;
  var f3=(){print("foo");};
  print(reflect(f1).function.hashCode); // 313080768
  print(reflect(f2).function.hashCode); // 313080768
  print(reflect(f3).function.hashCode); // 313080768

}

@alexmarkov
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