How to log an earlier captured stacktrace?

[rauhs]

Background: We have frequent DB context leaks. We have started recording (new StackTrace()) where the context was created and we dump some of the stack trace in:

    [Event(2)]
    public void ContextName(string name, string createdAt)
    {
      this.WriteEvent(2, name, createdAt);
    }
    protected override void OnEventCommand(EventCommandEventArgs command)
    {
      base.OnEventCommand(command);
      if (command.Command == EventCommand.Enable)
      {
        foreach (var entry in ContextDictionary.Instance.AllContexts)
        {
          this.ContextName(entry.ContextKey.ToString(), entry.StackTraceAsString);
        }
      }
    }

Seeing real tack traces for events is fantastic. So my question: Would it be possible to dump the stack trace as-is with the Event Source?

So that I could just press CTRL+S to see the exact stack.

[brianrob]

I'm not sure I fully understand, so please correct me if I go off in a different direction. There are a couple of ways that you can get stack traces through ETW. One is that each time an event is emitted, you can get the stack trace at the time and place of the event. Or, if for some reason you can't emit an event at the time and place of the stack, you can always use StackTrace to capture and save the stack, and then emit it as a string later. I'd like to believe that you can always use the first case, but I'm sure there are some cases where that's not true.

Hope that helps - let me know if I completely missed your question.

[rauhs]

Thanks for the reply. Sorry about being imprecise.

What I basically want is:

var stack = new StackTrace(); // NO perfview is running. We store the stacktrace somewhere.

// then later on, maybe 15min later we start perfView

EtwFooBar.Log.ContextWasCreatedAt(stack); // ideally we display it no as s string. But using the stack viewer of PerfView

I guess that this isn't possible. After all, the recoding of the stacktrace is done by the kernel, right?

Anyways, feel free to close this. It was a shot in the dark but I'm pretty sure this isnt possible. I guess I'll stick with a string-payload for the stack. :)

Cheers

[brianrob]

Now I understand - you're right, there isn't a good way to do this with just ETW because the stack that you want has to be captured before ETW tracing starts, and ETW is the thing that would capture the stack.

That said, if what you're really after is PerfView showing the stacks in the stack viewer, this is possible. What you'd do is capture the stack as you do today, and emit it into your own event. Then, you can implement a PerfView plugin that takes your events and builds a StackSource. You then surface that StackSource through your plugin in your own view.

This would give you the same type of behavior as the AnyStacks view. If you're just talking about one stack, this might not be worth it, but if you're trying to aggregate lots of stacks, then this could be worth your time.