[MT][browser] `System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests` fails

[ilonatommy]

After enabling all MT library tests (#91536)

[FAIL] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests
 RunContinueWhenAnyTests: > FAILED! continuation.Wait() should throw exception iff preCanceledToken
 Expected: True
 Actual:   False
   at System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests()
    at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
    at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

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Issue Details

---

After enabling all MT library tests (#91536)

[FAIL] System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests
 RunContinueWhenAnyTests: > FAILED! continuation.Wait() should throw exception iff preCanceledToken
 Expected: True
 Actual:   False
   at System.Threading.Tasks.Tests.TaskContinueWhenAnyTests.RunContinueWhenAnyTests()
    at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
    at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

Author:	ilonatommy
Assignees:	-
Labels:	arch-wasm, disabled-test, area-Build-mono, area-VM-threading-mono
Milestone:	-

[radekdoulik]

This is still valid issue.

Interestingly the test passes when run with the other tests.

When I run it separately, it deadlocks with:

  info: Initializing dotnet version 9.0.0-dev commit hash 75dc1b3cd2a92df13fdc383212d1c2d8a7928f19
  info: Discovering: System.Threading.Tasks.Tests.dll (method display = ClassAndMethod, method display options = None)
  info: Discovered:  System.Threading.Tasks.Tests.dll (found 1 of 787 test cases)
  info: Using random seed for test cases: 304684785
  info: Using random seed for collections: 304684785
  info: Starting:    System.Threading.Tasks.Tests.dll
  warn: Blocking on the main thread is very dangerous, see https://emscripten.org/docs/porting/pthreads.html#blocking-on-the-main-browser-thread
  warn: MONO_WASM [0xf3d3c-main]: Failed to find loaded WebWorker, this may deadlock. Please increase the pthreadPoolSize.

[pavelsavara]

how many threads we think it should use ? I see something like (2^6)*3 tasks being created, some of them long running.