Is there a way to get the stacktraces for all threads in c#, like java.lang.Thread.getAllStackTraces()?

Question

In java it is possible to get a snapshot of the stacktraces of all running threads. This is done with java.lang.Thread.getAllStackTraces() (it returns Map<Thread,StackTraceElement[]>).

How can this be done with .net?

Answer 1

So I actually just had to figure out how to do this -- haven't used this solution extensively in production yet, but theres a relatively new library called ClrMd.

http://blogs.msdn.com/b/dougste/archive/2013/05/04/clrmd-net-crash-dump-and-live-process-inspection.aspx

Using it, I'm able to attach to my own process and get a stack trace for all live threads. Using this when a deadlock is detected before restarting our app like so:

var result = new Dictionary<int, string[]>();

var pid = Process.GetCurrentProcess().Id;

using (var dataTarget = DataTarget.AttachToProcess(pid, 5000, AttachFlag.Passive))
{
    ClrInfo runtimeInfo = dataTarget.ClrVersions[0];
    var runtime = runtimeInfo.CreateRuntime();

    foreach (var t in runtime.Threads)
    {
        result.Add(
            t.ManagedThreadId,
            t.StackTrace.Select(f =>
            {
                if (f.Method != null)
                {
                    return f.Method.Type.Name + "." + f.Method.Name;
                }

                return null;
            }).ToArray()
        );
    }
}

var json = JsonConvert.SerializeObject(result);

zip.AddEntry("_threads.json", json);

The really important thing to get that to work from the same process is AttachFlag.Passive

If you just do DataTarget.AttachToProcess(pid, 5000), it'll do an "invasive" attach which attempts to pause the process. This throws an exception when you try to attach to your own process, I'm assuming because you can't pause your application while trying to attach from your application or something like that.