Memoryleak using Transformer when running pub serve about reflectable.dart

[zoechi]

Seems to be the same issue I run into

Missing entry point: web/forms/selecting_many_items_using_checkboxes/index.dart
Exhausted heap space, trying to allocate 586272 bytes.
Exhausted heap space, trying to allocate 96 bytes.
in ShutdownIsolate: Unhandled exception:
Uncaught Error: Out of Memory
Stack Trace:
#0 _AllMatchesIterator.moveNext (dart:core-patch/regexp_patch.dart:268)
#1 _StringBase.replaceFirst (dart:core-patch/string_patch.dart:573)
#2 getErrorMessage (package:$pub/utils.dart:20)
#3 CrossIsolateException.serialize (package:$pub/serialize/exception.dart:45)
#4 serializeException (package:$pub/serialize/exception.dart:88)
#5 respond. (package:$pub/serialize.dart:164)
#6 _RootZone.runBinary (dart:async/zone.dart:1170)
#7 _Future._propagateToListeners.handleError (dart:async/future_impl.dart:529)
#8 _Future._propagateToListeners (dart:async/future_impl.dart:588)
#9 _Future._completeError (dart:async/future_impl.dart:384)
#10 _SyncCompleter._completeError (dart:async/future_impl.dart:56)
#11 _Completer.completeError (dart:async/future_impl.dart:27)
#12 TransformerImplementation.apply.<apply_async_body> (package:reflectable/src/transformer_implementation.dart:2008)
#13 _Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:670)
#14 _Future._propagateToListeners (dart:async/future_impl.dart)
#15 _Future._asyncComplete. (dart:async/future_impl.dart:376)
#16 _microtaskLoopEntry (dart:async/schedule_microtask.dart)
#17 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart)

#0 _rootHandleUncaughtError. (dart:async/zone.dart:894)
#1 _microtaskLoop (dart:async/schedule_microtask.dart:43)
#2 _microtaskLoopEntry (dart:async/schedule_microtask.dart:52)
#3 _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:96)
#4 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:151)

After about 10-20 reloads I get this exception.

name: polymer_dart_samples
description: Port of https://github.com/PolymerLabs/polymer-snippets
environment:
  sdk: '>=1.2.0 <2.0.0'
dependencies:
  polymer_elements:
    git: [email protected]:dart-lang/polymer_elements.git
  web_components: ^0.12.0
  polymer: ^0.17.0
transformers:
- web_components:
    entry_points:
    - web/forms/binding_a_boolean_field_to_a_checkbox/index.html
    - web/forms/binding_to_a_text_input/index.html
    - web/forms/binding_to_a_textarea/index.html
    - web/forms/implementing_simple_autocompletion/index.html
    - web/forms/implementing_simple_validation/index.html
    - web/forms/selecting_one_item_using_radio_buttons/index.html
    - web/forms/selecting_many_items_using_checkboxes/index.html
   # - web/events/using_custom_events/index.html
    - web/styling_elements/applying_styles_by_piercing_shadow_dom_boundaries/index.html
    - web/styling_elements/defining_styles_inside_a_polymer_element/index.html
    - web/styling_elements/programmatically_changing_the_styles_of_an_element/index.html
    - web/styling_elements/styling_distributed_nodes/index.html
    - web/styling_elements/using_host_context_to_theme_an_element/index.html
    - web/styling_elements/using_host_with_a_css_selector/index.html
    - web/styling_elements/using_host_with_pseudo_classes/index.html
    - web/layout_attributes/nesting_flex_layouts/index.html
    - web/layout_attributes/using_flex/index.html
    - web/layout_attributes/using_layout_attributes/index.html
    - web/polymer_elements/paper_toolbar/adding_a_menu_button/index.html
    - web/polymer_elements/paper_toolbar/adding_button_rows/index.html
    - web/polymer_elements/paper_toolbar/changing_the_toolbar_size/index.html
    - web/polymer_elements/paper_toolbar/using_paper_toolbar/index.html
- reflectable:
    entry_points:
    - web/forms/binding_a_boolean_field_to_a_checkbox/index.dart
    - web/forms/binding_to_a_text_input/index.dart
    - web/forms/binding_to_a_textarea/index.dart
    - web/forms/implementing_simple_autocompletion/index.dart
    - web/forms/implementing_simple_validation/index.dart
    - web/forms/selecting_one_item_using_radio_buttons/index.dart
    - web/forms/selecting_many_items_using_checkboxes/index.dart
    - web/styling_elements/applying_styles_by_piercing_shadow_dom_boundaries/index.dart
    - web/styling_elements/defining_styles_inside_a_polymer_element/index.dart
    - web/styling_elements/programmatically_changing_the_styles_of_an_element/index.dart
    - web/styling_elements/styling_distributed_nodes/index.dart
    - web/styling_elements/using_host_context_to_theme_an_element/index.dart
    - web/styling_elements/using_host_with_a_css_selector/index.dart
    - web/styling_elements/using_host_with_pseudo_classes/index.dart
    - web/layout_attributes/nesting_flex_layouts/index.dart
    - web/layout_attributes/using_flex/index.dart
    - web/layout_attributes/using_layout_attributes/index.dart
- $dart2js:
    $include: '**/*.bootstrap.initialize.dart'
dependency_overrides:
  polymer:
    git:
      ref: aea190df60e6c9d20078d89919443dea8e1b1997
      url: https://github.com/dart-lang/polymer-dart.git
  polymer_interop:
    git:
      ref: 0.2.0-dev
      url: https://github.com/dart-lang/polymer_interop.git
  reflectable: 0.2.0

[sigurdm]

Thanks for the bug report.
This might be some caching gone astray.
But from the provided information it is hard to say exactly where the problem is.
Are you able to provide the program itself that causes the leak so we can investigate further?

[zoechi]

I had this a few times when I worked on https://github.com/bwu-dart-contributing/polymer-dart-patterns/tree/0.17.0/web/forms/implementing_simple_autocompletion
I haven't tried if simply reloading without changing anything leads to OOM.

[zoechi]

I updated the link, I forgot to link to the right branch (0.17.0).

[wienczny]

I don't think that reloading unchanged files causes this because the transformer is not running. I did a lot of reloads and nothing happens. If you want to trigger it even small changes to the code like add/removing a comment to a print statement will cause this behavior after some iterations.
If it's still necessary I will try to provide a stripped down example but that will take some time for preparation.

[eernstg]

I tried to perform a small experiment: I ran pub serve in polymer-dart-patterns and loaded http://localhost:8080/layout_attributes/nesting_flex_layouts/index in dartium, and then did touch web/layout_attributes/nesting_flex_layouts/index.dart every 20 seconds. This causes pub serve to re-transform at each touch for a while (saying 'Build completed successfully' about 9 times, then just '[Info from Reflectable..]' without 'Build'), and then it stopped (no more output in the terminal, anyway). At the same time we have a growing process (ps shows 10GB, 19GB, 28GB).

I'll experiment a little more with that.

[zoechi]

Looks similar to my experience. At first Dartium starts to time out and after a few more retries it crashes with OOM.

[wienczny]

@eernstg This should be the issue I'm experiencing.
@zoechi Is the OOM in Dartium, too?

[zoechi]

@wienczny I'm not sure what you mean by "in Dartium".
pub serve crashes with OOM and I use the reflectable transfomer only with Polymer 1.0.0-rc1 (client-side with Dartium).

[wienczny]

@zoechi I was not sure whether the "it" from your post referred to pub or Dartium.

[zoechi]

I found a similar issue. Might be related dart-archive/polymer-dart#401

[eernstg]

I just landed a commit (8fbd269) that changes the transformer in a tiny way syntactically, but it makes a difference in practice: The test scenario that I ran yesterday where pub serve serving 'http://localhost:8080/iron_validatable_behavior/index.html' to dartium could run 9 transformations before it started to fail now runs 150 transformations with no signs of trouble. The process still grows over time, but much less. The point is that we now use a single Resolvers instance rather than one per transformation.

[zoechi]

Sounds great!