Random Quiet Abends using WebBrowser2

[Lassesen]

Description
I have a WinForm application in C# that walks web sites (i.e. a web crawler). Logging performance, http code, sizes etc.

At random will will just die, no error message. I have built a resume on last work not done into the application and it proceeds fine.
In some cases, it will run for less than 100 pages before dying, in other cases almost 10,000 (on the same web site). So it does not appear to be a content issue.

The main issue is that the death is totally quiet,

Version

  <package id="log4net" version="2.0.14" targetFramework="net472" />
  <package id="Microsoft.AspNet.Mvc" version="5.2.9" targetFramework="net472" />
  <package id="Microsoft.AspNet.Razor" version="3.2.9" targetFramework="net472" />
  <package id="Microsoft.AspNet.WebPages" version="3.2.9" targetFramework="net472" />
  <package id="Microsoft.Web.Infrastructure" version="2.0.0" targetFramework="net472" />
  <package id="Microsoft.Web.WebView2" version="1.0.1264.42" targetFramework="net472" />
  <package id="System.Configuration.ConfigurationManager" version="6.0.0" targetFramework="net472" />
  <package id="System.Security.AccessControl" version="6.0.0" targetFramework="net472" />
  <package id="System.Security.Permissions" version="6.0.0" targetFramework="net472" />
  <package id="System.Security.Principal.Windows" version="5.0.0" targetFramework="net472" />
  <package id="System-Web-Helpers.dll" version="1.0.0" targetFramework="net472" />

Repro Steps

{
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.ThreadException += ThreadException;

            // Set the unhandled exception mode to force all Windows Forms errors to go through
            // our handler.
            Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);

            // Add the event handler for handling non-UI thread exceptions to the event.
            AppDomain.CurrentDomain.UnhandledException += UnhandledException;

            try
            {
                Application.Run(new Form1());
            }
            catch (Exception exc)
            {
                log.Error(exc);
            }
        } )

Additional context

[aluhrs13]

@Lassesen - Are you listening to WebView2's ProcessFailed event at all? If WV2 is crashing that would give you an error code and other information for us to look at.

[Lassesen]

Yes, I am -- I went on an event linking marathon trying to resolve it, to no avail.

I have a workaround, a CMD file doing an infinite loop that picks up from SQL the next item to walk... so when it dies, it restarts and resumes...

  private void Edge_ProcessFailed(object sender, CoreWebView2ProcessFailedEventArgs e)
        {
            listBoxEvents.Items.Add("Edge_ProcessFailed");
            RecordError($"[190] {e.ProcessFailedKind}:{e.Reason}:{e.ProcessDescription}:{e.ExitCode}\t{_requestNumber}\t{edge.Source.AbsoluteUri} ");
            MarkRequestDone();
        }

[aluhrs13]

That's really odd - And you're using the same WV2 for all of this (assuming it doesn't disappear) or are you making a new WV2 for every URL you crawl?

Are there any files in the \EBWebView\Crashpad\reports folder of your app's user data folder?

[Lassesen]

I am using the same WV2 (I am crawling a site that requires sign on and uses session variables)
Yes there are, I have zipped the entire folder.

(edited by Andy to remove the files that might have sensitive information)

[aluhrs13]

You're hitting an out of memory error, without more details of what's happening in the loop it's hard to tell exactly what's causing it. Would you be willing to share the source with me? (can take this offline in email, aluhrs at microsoft.com) Memory leaks in a platform like WebView2 are hard to track down and reproduce, so if you're hitting something in our code that's causing this that would be REALLY helpful and could help a lot of other apps in the process.

[Lassesen]

Sending you a zip file. You should be able to adapt it.

[Lassesen]

As a FYI on my prior issues. The problems I encountered were only when running from visual studio (i.e. debug). It runs stable for 96+ hrs when executed from the build image without Visual Studio

[aluhrs13]

Sorry for not following up, I was out of office for a few months soon after this.

I wasn't able to repro with what you shared, and it seems like it might be related to debug build which is likely out of our control. Will close in ~7 days unless you disagree.