Roslyn: Visual Studio 16.4 deadlocks when saving files.

[JohanLarsson]

It happens a couple of times per day. The deadlock happens before files are written to disk so work is lost.

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
  <PropertyGroup>
    <TargetFrameworks>net45;netcoreapp3.0</TargetFrameworks>
    <UseWpf>true</UseWpf>
    <GenerateDocumentationFile>true</GenerateDocumentationFile>
  </PropertyGroup>

Don't have much info other than that this bug showed up in 16.4 and a suspicion that it might have something to do with multitargeted WPF control libraries.

I have tried waiting 30 minutes but no dice.

[Insire]

I encountered deadlogs aswell, while working with a multitargetting wpf project. Especially easy to reproduce, when i open a solution and immediately hit the save button in VS.

[JohanLarsson]

Other times I have seen it happen is when editing project files in the xml editor.

[patrickklaeren]

Have had issues when saving after moving files, and fixing namespaces in multiple .NET Framework and .NET Standard class libraries in a solution with WPF projects (not sure that matters). VS locks up and stops responding.

[CyrusNajmabadi]

I've run into this myself. @jinujoseph this may be another report of hte hang i reported here: https://github.com/dotnet/roslyn/issues/40233

Note: this issue is critical as it does lead to data-loss.

[Trinitek]

I've experienced this deadlock on two projects. The first is a WPF project that multi-targets net47 and netcoreapp3.0. The second is a WPF project that targets net462.

[Insire]

It was on a multi project solution for me, where i was targetting net461;netcoreapp3.0, netcoreapp3.0 and netstandard2.0 in separate projects. It can be found here. I encountered it also on a project that was only targetting net472 at work. All of them were using the new project style format.

[sharwell]

@JohanLarsson Can you file an issue on developer community for this? The instructions for this type of hang can be found here:
https://docs.microsoft.com/en-us/visualstudio/ide/how-to-increase-chances-of-performance-issue-being-fixed?view=vs-2019#unresponsiveness

[JohanLarsson]

I'll try to remember to fire up another instance and report. Didn't know that option existed.

[JohanLarsson]

@sharwell recorded and reported now.

[CyrusNajmabadi]

@sharwell Reported issue by johan is here: https://developercommunity.visualstudio.com/content/problem/852667/visual-studio-hangs-forever-when-saving-files.html

Johan, can you include the repro steps you identified in our gitter chat?

[CyrusNajmabadi]

@mavasani Can you take a look ? Ths is a significant data loss issue as this literally happens during save. So users explicitly lose whatever they were working on and the product must be killed/restarted.

[JohanLarsson]

Repro using 16.4.2

1. Create a new WPF netcore project.
2. Edit two files (I removed the unused usings in App.Xaml.cs and MainWindow.xaml.cs)
3. Click save all

[JohanLarsson]

https://developercommunity.visualstudio.com/content/problem/852667/visual-studio-hangs-forever-when-saving-files.html

[CyrusNajmabadi]

@mavasani and @sharwell , @JohanLarsson has linked to vsfeedback issue containing the traces here. can you look asap. this is a data-loss and complete product hang issue.

tagging @jinujoseph @vatsalyaagrawal for visbility. This was reported nearly two weeks ago, but has no one assigned to it.

Milestone was also put at 'backlog', even though this should be a pri0 issue looked into immediately.

[mavasani]

Investigating..

[mavasani]

@JohanLarsson I noticed from the report that you have 16.4.1 installed. Can you also try to quickly upgrade to 16.4.2, in case it is same issue as https://github.com/dotnet/roslyn/issues/40455#issuecomment-566851545?

[JohanLarsson]

Repro with 16.4.1 and 16.4.2

[CyrusNajmabadi]

@mavasani he also reproed it on 16.4.2 as per gitter and https://github.com/dotnet/roslyn/issues/40241#issuecomment-567700873

[CyrusNajmabadi]

@JohanLarsson will also be linking to a direct 32bit dump produced from devenv.

[mavasani]

Looks like a dupe of https://github.com/Xavalon/XamlStyler/issues/216

UI thread:

    win32u.dll!_NtUserMsgWaitForMultipleObjectsEx@20
()  Unknown
    user32.dll!763adfd9()   Unknown
    user32.dll![Frames below may be incorrect and/or missing, no symbols loaded for user32.dll] Unknown
    user32.dll!763adf0d()   Unknown
    msenv.dll!ATL::AtlInternalQueryInterface(void *,struct ATL::_ATL_INTMAP_ENTRY const *,struct _GUID const &,void * *)    Unknown
    msenv.dll!CPropertiesImpl::IsOnlyReferencedByItsChildrenAndViceVersa(void)  Unknown
    [Waiting on lock owned by Thread 23264] 
    [Managed to Native Transition]  
    WindowsBase.dll!System.Windows.Threading.DispatcherSynchronizationContext.Wait(System.IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)  Unknown
    mscorlib.dll!System.Threading.SynchronizationContext.InvokeWaitMethodHelper(System.Threading.SynchronizationContext syncContext, System.IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)    Unknown
    [Native to Managed Transition]  
    [Managed to Native Transition]  
    System.dll!System.ComponentModel.Container.Components.get() Line 165    C#
>   Microsoft.VisualStudio.Shell.15.0.dll!Microsoft.VisualStudio.Shell.Package.GetDialogPage(System.Type dialogPageType)    Unknown
    XamlStyler3.Package.dll!Xavalon.XamlStyler3.Package.StylerPackage.Execute(EnvDTE.Document document) Unknown
    XamlStyler3.Package.dll!Xavalon.XamlStyler3.Package.StylerPackage.OnFileSaveAllBeforeExecute.AnonymousMethod__9_0(EnvDTE.Document document) Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForEachWorker.AnonymousMethod__0(int i)    Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForWorker.AnonymousMethod__1() Unknown
    mscorlib.dll!System.Threading.Tasks.Task.InnerInvoke()  Unknown
    mscorlib.dll!System.Threading.Tasks.Task.InnerInvokeWithArg(System.Threading.Tasks.Task childTask)  Unknown
    mscorlib.dll!System.Threading.Tasks.Task.ExecuteSelfReplicating.AnonymousMethod__0(object <p0>) Unknown
    mscorlib.dll!System.Threading.Tasks.Task.ExecuteSelfReplicating(System.Threading.Tasks.Task root)   Unknown
    mscorlib.dll!System.Threading.Tasks.Task.Execute()  Unknown
    mscorlib.dll!System.Threading.Tasks.Task.ExecutionContextCallback(object obj)   Unknown
    mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx)   Unknown
    mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx)   Unknown
    mscorlib.dll!System.Threading.Tasks.Task.ExecuteWithThreadLocal(ref System.Threading.Tasks.Task currentTaskSlot)    Unknown
    mscorlib.dll!System.Threading.Tasks.Task.ExecuteEntry(bool bPreventDoubleExecution) Unknown
    mscorlib.dll!System.Threading.Tasks.ThreadPoolTaskScheduler.TryExecuteTaskInline(System.Threading.Tasks.Task task, bool taskWasPreviouslyQueued)    Unknown
    mscorlib.dll!System.Threading.Tasks.TaskScheduler.TryRunInline(System.Threading.Tasks.Task task, bool taskWasPreviouslyQueued)  Unknown
    mscorlib.dll!System.Threading.Tasks.Task.InternalRunSynchronously(System.Threading.Tasks.TaskScheduler scheduler, bool waitForCompletion)   Unknown
    mscorlib.dll!System.Threading.Tasks.Task.RunSynchronously(System.Threading.Tasks.TaskScheduler scheduler)   Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForWorker<object>(int fromInclusive, int toExclusive, System.Threading.Tasks.ParallelOptions parallelOptions, System.Action<int> body, System.Action<int, System.Threading.Tasks.ParallelLoopState> bodyWithState, System.Func<int, System.Threading.Tasks.ParallelLoopState, object, object> bodyWithLocal, System.Func<object> localInit, System.Action<object> localFinally)    Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForEachWorker<EnvDTE.Document, object>(System.Collections.Generic.IList<EnvDTE.Document> list, System.Threading.Tasks.ParallelOptions parallelOptions, System.Action<EnvDTE.Document> body, System.Action<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState> bodyWithState, System.Action<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, long> bodyWithStateAndIndex, System.Func<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, object, object> bodyWithStateAndLocal, System.Func<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, long, object, object> bodyWithEverything, System.Func<object> localInit, System.Action<object> localFinally)    Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForEachWorker<EnvDTE.Document, object>(System.Collections.Generic.IEnumerable<EnvDTE.Document> source, System.Threading.Tasks.ParallelOptions parallelOptions, System.Action<EnvDTE.Document> body, System.Action<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState> bodyWithState, System.Action<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, long> bodyWithStateAndIndex, System.Func<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, object, object> bodyWithStateAndLocal, System.Func<EnvDTE.Document, System.Threading.Tasks.ParallelLoopState, long, object, object> bodyWithEverything, System.Func<object> localInit, System.Action<object> localFinally)    Unknown
    mscorlib.dll!System.Threading.Tasks.Parallel.ForEach<EnvDTE.Document>(System.Collections.Generic.IEnumerable<EnvDTE.Document> source, System.Action<EnvDTE.Document> body)  Unknown
    XamlStyler3.Package.dll!Xavalon.XamlStyler3.Package.StylerPackage.OnFileSaveAllBeforeExecute(string guid, int id, object customIn, object customOut, ref bool cancelDefault)    Unknown
    EnvDTE.dll!EnvDTE._dispCommandEvents_SinkHelper.BeforeExecute(string A_1, int A_2, object A_3, object A_4, ref bool A_5)    Unknown

[mavasani]

@JohanLarsson Fine with me closing this as external?

[JohanLarsson]

Ah, thanks!

[CyrusNajmabadi]

Thanks for the quick workaround @mavasani !