Failure in lib/async/timer_isActive_test on Chrome 41 on macos

[whesse]

The test lib/async/timer_isActive_test is failing with a runtime error, 3 times out of 10 on the chrome macos buildbot, since Chrome was updated to version 41.

The error is in the "timer cancel test" subtest:

             type: print
              value: FAIL: timer cancel test
                      Should not be reached.
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 2634:15 dart.wrapException
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 12409:17 SimpleConfiguration.dart.SimpleConfiguration.onExpectFailure$1
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 12374:20 _ExpectFailureHandler.dart._ExpectFailureHandler.fail$1
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 11929:22 main__closure0.dart.main__closure0.call$0
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 5109:16 dart._rootRun
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 6803:39 _CustomZone.dart._CustomZone.run$1
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 6716:19 _CustomZone.dart._CustomZone.runGuarded$1
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 6898:26 _CustomZone_bindCallback_closure.dart._CustomZone_bindCallback_closure.call$0
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 5112:14 dart._rootRun
                      http://127.0.0.1:57228/root_build/generated_compilations/dart2js-sdk/tests_lib_async_timer_isActive_test/test.js 6803:39 _CustomZone.dart._CustomZone.run$1
              timestamp: 9.027

[lrhn]

Could it be caused by resent timer changes?

---

cc @iposva-google.

[whesse]

This is a failure on Chrome, with dart2js compiled tests, so I don't think timer changes in the VM would do anything.

There are also timeouts on async/slow_consumer_test and async/catch_errors11_test.

[whesse]

We have timeouts on many async tests on Mac Chrome dart2js. These tests are running slowly in the cases that they don't time out, so there is something making them slow, and highly variable in the time they take. For example, async_await_test/03 takes 18 seconds on one run, 50 seconds on another, and times out with > 60 seconds on 2 more runs.

Here are the additional tests that are marked as timing out in the language.status status file:
language/async_await_test/none: Pass, Timeout # Issue #22695.
language/async_await_test/02: Pass, Timeout # Issue #22695.
language/async_await_test/03: Pass, Timeout # Issue #22695.

[floitschG]

Fwiw I tried the async_await tests on Chrome Linux and there it is really fast.
This seems to be a Mac only issue :(

The timer_isActive_test was relying on the assumption that it wouldn't take more than a second to schedule two asynchronous operations.
The fact that it failed, indicates that just scheduling an asynchronous operation is very slow on Chrome Mac.

A few days ago I updated the test (without knowing about this bug here):
https://codereview.chromium.org//994013002

[matanlurey]

This is a browser from years ago.