I have a .NET Windows service that appears to be crashing due to C00000005 (access violation--according to Dr Watson). When I attach the VS debugger to it--whether I build it with or without symbols--the VS debugger just stops when the service crashes, instead of stopping to give me a chance to do any investigation.
Is that to be expected, or am I doing something wrong?
Will using WinDbg let me do something more in real time (obviously, WinDbg lets me do crash dump analysis)?
Thanks!
You should go to the exceptions window (Debug -> Exceptions) and select the Thrown check box for that exception in the Win32 Exceptions. Moreover, pay attention that you are debugging Native Code (see the attached to combo box in the attach to process window.
Related
I want to capture a stacktrace of an application which sometimes stops responding for few minutes.
When the application stops responding, the windows desktop also stops responding to mouse clicks, although some other already running applications are working fine at that time (for example windbg works fine, ProcessExplorer refreshes its screen, but does not respond to mouse events).
While the application is non responsive, it is actually taking about 80% of one CPU core. That is why I would like to get a stacktrace.
The misbehaving application usually takes about 2-3 minutes to do its strange job or if Ctrl+Esc is pressed it becomes responsive immediately (and the start menu opens of course...)
I have WinDbg attached to the misbehaving application and when I issue the Break command, the break-in does not happen until the application starts to respond again.
From what I understand the break-in actually creates a remote thread which pretty soon calls DbgBreakPoint.
What could be preventing debugger's thread from executing?
EDIT:
First of all thanks for your help!
I was also thinking that this might be caused by a bad device driver or something that installs a system wide hook somewhere.
I was thinking to enable kernel debugging and get a stack trace from the kernel for the offending thread or enable manual bluescreen trigger to produce a dump and look at that afterwards.
Process Explorer and Process Monitor does not reveal anything interesting. They also become unusable when the bug is triggered (updating their windows but not responsive to mouse or keyboard).
EDIT2:
Background info:
App uses QT, OpenGL and also DirectSound and runs on Windows 7 SP1 x64
I am currently suspecting something with the graphics part.
The strange thing is that if a system-wide lock is taken (like GDI Lock), this would prevent drawing of other Windows, but that does not happen. WinDbg on same machine works fine. ProcessExplorer updates but does not receive mouse clicks, Desktop updates but no mouse clicks.
I currently have a kernel debugger attached...
EDIT3
ETW was most useful for debugging. It turns out that Qt's main event processing loop goes crazy. PeekMessage and MsgWaitForMultipleObjectsEx (with 0 timeout) gets called in a tight loop. That is where the high CPU usage comes from.
It looks like the App is generating/getting loads of messages at that time. But it is not easy to see what the messages are (or I don't know how to access function parameters in ETW). Using a debugger also does not help much but, with a breakpoint in the QT's event loop leads me to believe that WM_TIMER messages are the culprit.
Given that the desktop also misbehaves during this time, it sounds like your app isn't necessarily misbehaving but merely aggravating a bug elsewhere (e.g., in a device driver or some crummy anti-malware code that has injected itself into other processes). Stack traces from your app may or may not be very revealing.
If the problem is easily reproducible, I'd set a breakpoint somewhere in the "middle" of the app and see if the problem happens before or after that. Then move the breakpoint until you find the last instruction your app executes before things go bonkers. Figuring out what your app does that triggers this behavior may give a clue as what's going on.
Another option is to try using some system-wide debugging tools. First, I'd peak in the Event Viewer to see if there are suspicious error or warning events posting in proximity to the moment the machine goes haywire. Then I'd try a tool like Sysinternal's Process Monitor or Process Explorer to get a better view of what's happening. You might also try ETW to capture a system-wide trace of what's happening on the system that you can study after the fact. (ETW can be hard to use, so check out Bruce Dawson's UIforETW.)
Use ETW to find the cause. Install the Windows Performance Toolkit (part of the Win10 v1511 SDK: https://go.microsoft.com/fwlink/p/?LinkID=698771 which is the last version that works in Win7), run WPRUI.exe, select CPU Usage and click on Start.
After you captured the hang, click on Save. Wait until WPRUI is finished, open the ETL in WPA, setup and load debug symbols in WPA.
Drag & Drop the CPU Usage (Precise) graph to analyse pane and look for WAIT (µs) max for your process to see that long hang and expand the stack to see where it happens.
Win7 Directx 11 with VS 2012 -- When I let my app run in full screen on my development computer, eventually, the program exits full screen back to windowed, all by itself, and pops up a dialog telling me windows resources are running low. The dialog tells me something about turning off interactive themes or something to that end. When I run the program in release mode on one of our client machines, the app runs fine, does everything it should, but after a while, instead of popping up the dialog about windows resources, I get an exception window with exception 0x40000015 as the error. This only happens if I am in full screen, windowed, it never crashes. Event Viewer shows nothing at all about the crash. Any thoughts?
Thanks in advance. Basically what my app is, is a wrapper graphics library. When it says I am using all the resources, my resource monitor shows that I never went above 20% of memory and the cpu never went above 14%. The 0x40000015 error number is rather general and doesn't exactly point me in any real direction.
This is not related to trying to exit an app in full screen, as that I have the code required to prevent the exception related to that problem.
R
It turned out to be a component issue on the target platform. The ReportLiveDeviceObjects info was helpful and will continue to help down the line.
I have a hub application that is responsible for handling the launching of three other programs. I am having considerable difficulty with this - When I launch one of the three alone, everything is fine; when I try to run them from the main hub application, they crash.
I need to figure out how I can keep the hub open, and open the process I start with the debugger after it launches right off, so I can catch the issues and debug it properly.
To give an example for how I am starting the processes from the main program -
this.Hide( );
Process.Start( FilePath).WaitForExit( );
Process.GetCurrentProcess( ).Kill( );
Visual Studio has a setup that allows it to debug any application that crashes before calling ExitProcess() and in case the process threw an exception, if the exception is not caught (i.e. try + catch(...) + exit(1)).
I always let the installer turn on that feature, but if you have it turned off, you should be able to turn it back on by going in the settings. Once one, on a crash, you get a message box asking you whether you want to debug the crashing process.
Does anyone ever use vs just-in-time debugger on Firefox plugin-container.exe?
I want to debug my Firefox plugin on start-up, so I try the just-in-time debugger on plugin-container.exe. I expect once the plugin-container.exe is running, it will trigger the debugger, when I can start VS to debug it.
However, I met the following error, and it happens on each plugin I try to load.
What is wrong here? I am using Firefox 23.0.1
You can't launch the plugin-container.exe with the JIT debugger; what you can do is connect to it after it launches. The easiest way to do this is to add a Sleep(10000) in the NP_Initialize or DllMain functions so that you have time to connect the debugger to the process.
As Georg suggested, the tips page he linked to has some other ideas you could use.
Visual Studio 2005 C++
Windows XP Pro
I have a sample application that I am testing, that links with boost libraries.
However, the program runs ok. However, when I try and stop the program by clicking the 'Stop Debugging' button. The program ends, but the console window remains open. So I have many of them, as during my testing I am starting and stopping the application.
Even when I try and close it by clicking the close button it has no affect. And it doesn't seem to appear under task manager when the program ends.
The only way I can close them if I reboot windows.
I am thinking it might be a thread that has not closed, and maybe that is keeping the console windows open.
Many thanks for any advice,
I have also seen this issue, I think it happens when a mutex or semaphore is still locked, or a thread hasn't cleanly exited. The only way I've found to prevent this is to make sure all mutexes/ semaphores/threads are cleaned up after before stopping the debugger.
Also it's interesting to note that this problem doesn't happen on Windows 7 or Linux. I have tried stopping the same program at the same places and the program always cleanly exits.
Good luck and happy coding!