问题
I am getting this error in my event logs for a service I put into production:
An unhandled win32 exception occurred in RivWorks.FeedHandler.exe [5496]. Just-In-Time debugging this exception failed with the following error: Debugger could not be started because no user is logged on.
I have it installed and running under a Win NT global account. I have no idea why it is trying to drop into debugging mode. It was built under the Release model. Running on the 4.0 Framework.
When I run on my dev machine, via an EXE entry point instead of the WinSvc entry point, everything runs just fine - BUT - I am already in "debug" mode.
Any ideas of what to look for?
2010-10-21 - NOTE - Changed the code base.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.IO;
using sysIO = System.IO;
using RivWorks.FeedHandler;
using System.Collections;
namespace RivWorks.FeedHandler.Service
{
public partial class FeedListener : ServiceBase
{
#region Declarations
private List<string> _keys = new List<string>();
private System.Threading.Timer _clock = null;
private FileSystemWatcher _watcher;
private BackgroundWorker _worker;
private Queue<string> _queue = new Queue<string>();
private bool _isDequeueing = false;
#endregion
#region Constructor
public FeedListener()
{
InitializeComponent();
}
#endregion
#region Start/Stop
protected override void OnStart(string[] args)
{
try
{
WriteToEventLog("Enter Start", EventLogEntryType.Information);
_keys.AddRange(new string[] { "csv", "xml", "zip", "rivx" });
_worker = new BackgroundWorker();
_worker.WorkerReportsProgress = true;
_worker.WorkerSupportsCancellation = true;
_worker.DoWork += new DoWorkEventHandler(BackgroundWorkerDoWork);
_worker.ProgressChanged += new ProgressChangedEventHandler(BackgroundWorkerProgressChanged);
_worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorkerRunWorkerCompleted);
_watcher = new FileSystemWatcher(AppSettings.Default.FTPRootPath, "*.*");
_watcher.IncludeSubdirectories = true;
_watcher.NotifyFilter = sysIO.NotifyFilters.DirectoryName | sysIO.NotifyFilters.FileName | sysIO.NotifyFilters.LastAccess | sysIO.NotifyFilters.CreationTime | sysIO.NotifyFilters.LastWrite;
_watcher.Created += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.Changed += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.EnableRaisingEvents = true;
// check every 15 minutes...
_clock = new System.Threading.Timer(Tick, null, 0, 900000);
WriteToEventLog("Exit Start", EventLogEntryType.Information);
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
this.Stop();
}
}
protected override void OnStop()
{
try
{
_watcher.Dispose();
_watcher = null;
_clock.Dispose();
_clock = null;
_worker.Dispose();
_worker = null;
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Event Handlers
void fileCreatedOrChanged(object sender, sysIO.FileSystemEventArgs e)
{
try
{
WriteToEventLog("Enter fileCreatedOrChanged", EventLogEntryType.Information);
if (!_queue.Contains(e.FullPath))
_queue.Enqueue(e.FullPath);
if (!_isDequeueing)
DeQueue();
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Do work on another Thread
void BackgroundWorkerDoWork(object sender, DoWorkEventArgs e)
{
try
{
WriteToEventLog("Enter BackgroundWorkerDoWork", EventLogEntryType.Information);
BackgroundWorker bw = sender as BackgroundWorker;
WriteToEventLog("Create Handler", EventLogEntryType.Information);
RivWorks.FeedHandler.Library.Handler handler = new RivWorks.FeedHandler.Library.Handler(Convert.ToBoolean(AppSettings.Default.InProduction), AppSettings.Default.ArchivePath);
WriteToEventLog("Setup Handler", EventLogEntryType.Information);
handler.Keys = _keys;
handler.RootDirectory = AppSettings.Default.RootDirectory;
handler.FtpPath = AppSettings.Default.FTPRootPath;
handler.WorkPath = AppSettings.Default.WorkPath;
handler.ArchivePath = AppSettings.Default.ArchivePath;
handler.EmailHost = AppSettings.Default.EmailHost;
handler.EmailPassword = AppSettings.Default.EmailPassword;
handler.EmailUser = AppSettings.Default.EmailUser;
handler.ErrorNotificationRecipients = AppSettings.Default.ErrorNotificationRecipients;
handler.InProduction = Convert.ToBoolean(AppSettings.Default.InProduction);
Library.DTO.FileHandler fileHandler = new Library.DTO.FileHandler(handler.FtpPath, handler.WorkPath, handler.ArchivePath, (string)e.Argument);
WriteToEventLog("Call Handler.Execute", EventLogEntryType.Information);
handler.Execute(bw, e, fileHandler);
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
finally
{
WriteToEventLog("Exit BackgroundWorkerDoWork", EventLogEntryType.Information);
}
}
void BackgroundWorkerProgressChanged(object sender, ProgressChangedEventArgs e)
{
try
{
if (e.ProgressPercentage >= 100)
{
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
void BackgroundWorkerRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
try
{
if (e.Cancelled)
{
WriteToEventLog("Cancelled.", EventLogEntryType.Warning);
if (e.Error != null)
{
WriteToEventLog(e.Error, EventLogEntryType.Error);
}
}
else if (e.Error != null)
{
WriteToEventLog(e.Error, EventLogEntryType.Error);
}
else
{
WriteToEventLog("Successfully completed.", EventLogEntryType.Information);
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Private Methods
private void Tick(object data)
{
try
{
if (!_isDequeueing)
{
WriteToEventLog("Enter Tick. FTP Root = " + AppSettings.Default.FTPRootPath, EventLogEntryType.Information);
foreach (string key in _keys)
{
List<string> files = Directory.GetFiles(Path.Combine(AppSettings.Default.FTPRootPath), "*." + key, SearchOption.AllDirectories).ToList();
foreach (string fileName in files)
{
if (File.Exists(fileName))
{
// Toss this file name into the Queue...
WriteToEventLog("Call _queue.Enqueue(" + fileName + ")", EventLogEntryType.Information);
if (!_queue.Contains(fileName))
_queue.Enqueue(fileName);
}
}
}
// Now, start handling the list of files...
DeQueue();
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
finally
{
WriteToEventLog("Exit Tick", EventLogEntryType.Information);
}
}
private void DeQueue()
{
try
{
_isDequeueing = true;
WriteToEventLog("Enter DeQueue", EventLogEntryType.Information);
while (_queue.Count > 0)
{
string queuedFile = _queue.Dequeue();
WriteToEventLog("DeQueued " + queuedFile, EventLogEntryType.Information);
bool isValid = false;
foreach (string key in _keys)
{
if (Path.GetExtension(queuedFile).Replace(".", "").Equals(key, StringComparison.CurrentCultureIgnoreCase))
isValid = true;
}
if (isValid)
{
// Now, spin up a new thread and do the work on the file, based on file type...
WriteToEventLog("Call RunWorkerAsync", EventLogEntryType.Information);
string UserName = Path.GetDirectoryName(queuedFile).Replace(AppSettings.Default.FTPRootPath, "").Replace("\\", "");
int i = 0;
DateTime sTime = DateTime.Now;
DateTime eTime = DateTime.Now;
_worker.RunWorkerAsync(queuedFile); // goes to BackgroundWorkerDoWork(object sender, DoWorkEventArgs e) //
while(_worker.IsBusy)
{
System.Threading.Thread.Sleep(5000);
i++;
}
eTime = DateTime.Now;
TimeSpan ts = new TimeSpan(eTime.Ticks - sTime.Ticks);
string msg = String.Format("Import for {0} started at {1} and ended at {2}. It took {3} cycles and the elapsed time was {4}:{5}:{6}.", UserName, sTime, eTime, i, ts.Hours, ts.Minutes, ts.Seconds);
WriteToEventLog(msg, EventLogEntryType.Information);
}
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
finally
{
_isDequeueing = false;
WriteToEventLog("Exit DeQueue", EventLogEntryType.Information);
}
}
private void WriteToEventLog(Exception ex, EventLogEntryType eventLogEntryType)
{
try
{
string message = string.Empty;
string sTrace = ex.StackTrace;
while (ex != null)
{
message = message + Environment.NewLine + Environment.NewLine + ex.Message;
ex = ex.InnerException;
}
message = message + Environment.NewLine + Environment.NewLine + sTrace;
WriteToEventLog(message, eventLogEntryType);
}
catch (Exception ex2)
{
WriteToEventLog(ex2.Message, EventLogEntryType.Error);
}
}
private void WriteToEventLog(string message, EventLogEntryType eventLogEntryType)
{
try
{
this.EventLog.WriteEntry(message, eventLogEntryType);
}
catch (Exception ex)
{
throw ex;
}
}
#endregion
}
}
2010-10-20 - NOTE - Added the Service code file. Maybe there is an elementary mistake in here?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.IO;
using sysIO = System.IO;
using RivWorks.FeedHandler;
namespace RivWorks.FeedHandler.Service
{
public partial class FeedListener : ServiceBase
{
#region Declarations
private List<string> _keys = new List<string>();
private System.Threading.Timer _clock = null;
private FileSystemWatcher _watcher;
private BackgroundWorker _worker;
static private bool _isBusy = false;
#endregion
#region Constructor
public FeedListener()
{
InitializeComponent();
}
#endregion
#region Start/Stop
protected override void OnStart(string[] args)
{
try
{
_keys.AddRange(new string[] { "csv", "xml", "zip", "rivx" });
_worker = new BackgroundWorker();
_worker.WorkerReportsProgress = true;
_worker.WorkerSupportsCancellation = true;
_worker.DoWork += new DoWorkEventHandler(BackgroundWorkerDoWork);
_worker.ProgressChanged += new ProgressChangedEventHandler(BackgroundWorkerProgressChanged);
_worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorkerRunWorkerCompleted);
_watcher = new FileSystemWatcher(AppSettings.Default.FTPRootPath, "*.*");
_watcher.IncludeSubdirectories = true;
_watcher.NotifyFilter = sysIO.NotifyFilters.DirectoryName | sysIO.NotifyFilters.FileName | sysIO.NotifyFilters.LastAccess | sysIO.NotifyFilters.CreationTime | sysIO.NotifyFilters.LastWrite;
_watcher.Created += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.Changed += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.EnableRaisingEvents = true;
// check every 5 minutes...
_clock = new System.Threading.Timer(Tick, null, 0, 300000);
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
this.Stop();
}
}
protected override void OnStop()
{
try
{
_watcher.Dispose();
_watcher = null;
_clock.Dispose();
_clock = null;
_worker.Dispose();
_worker = null;
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Event Handlers
void fileCreatedOrChanged(object sender, sysIO.FileSystemEventArgs e)
{
try
{
DTO.BackgroundWorkerEventArgs eventArgs = new DTO.BackgroundWorkerEventArgs();
sysIO.WatcherChangeTypes myType = e.ChangeType;
bool isValid = false;
foreach (string key in _keys)
{
if (Path.GetExtension(e.FullPath).Replace(".", "").Equals(key, StringComparison.CurrentCultureIgnoreCase))
isValid = true;
}
if (isValid)
{
eventArgs.PathAndFile = e.FullPath;
eventArgs.Key = Path.GetExtension(e.FullPath).ToLower().Replace(".", "");
eventArgs.FileName = Path.GetFileName(e.FullPath);
eventArgs.Path = Path.GetDirectoryName(e.FullPath);
eventArgs.UserName = Path.GetDirectoryName(e.FullPath).Replace(AppSettings.Default.FTPRootPath, "").Replace("\\", "");
eventArgs.IsRunning = true;
System.Threading.Thread.Sleep(30000);
// Now, spin up a new thread and do the work on the file, based on file type...
_isBusy = true;
_worker.RunWorkerAsync(eventArgs); // goes to BackgroundWorkerDoWork(object sender, DoWorkEventArgs e) //
int i = 0;
DateTime sTime = DateTime.Now;
DateTime eTime = DateTime.Now;
while (_isBusy)
{
System.Threading.Thread.Sleep(5000);
i++;
}
eTime = DateTime.Now;
TimeSpan ts = new TimeSpan(eTime.Ticks - sTime.Ticks);
string msg = String.Format("Import for {0} started at {1} and ended at {2}. It took {3} cycles and the elapsed time was {4}:{5}:{6}.", eventArgs.UserName, sTime, eTime, i, ts.Hours, ts.Minutes, ts.Seconds);
WriteToEventLog(msg, EventLogEntryType.Information);
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Do work on another Thread
void BackgroundWorkerDoWork(object sender, DoWorkEventArgs e)
{
try
{
RivWorks.FeedHandler.Handler handler = new RivWorks.FeedHandler.Handler();
BackgroundWorker bw = sender as BackgroundWorker;
handler.Execute(bw, e);
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
finally
{
_isBusy = false;
}
}
void BackgroundWorkerProgressChanged(object sender, ProgressChangedEventArgs e)
{
try
{
if (e.ProgressPercentage >= 100)
{
_isBusy = false;
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
void BackgroundWorkerRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
try
{
if (e.Cancelled)
{
WriteToEventLog("Cancelled.", EventLogEntryType.Warning);
if (e.Error != null)
{
WriteToEventLog(e.Error, EventLogEntryType.Error);
}
}
else if (e.Error != null)
{
WriteToEventLog(e.Error, EventLogEntryType.Error);
}
else
{
WriteToEventLog("Successfully completed.", EventLogEntryType.Information);
}
_isBusy = false;
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
#region Private Methods
private void Tick(object data)
{
try
{
foreach (string key in _keys)
{
List<string> files = Directory.GetFiles(Path.Combine(AppSettings.Default.FTPRootPath), "*." + key, SearchOption.AllDirectories).ToList();
foreach (string fileName in files)
{
System.Threading.Thread.Sleep(5000);
if (File.Exists(fileName))
{
DateTime lat = File.GetLastWriteTime(fileName);
try
{
File.SetLastWriteTime(fileName, DateTime.Now);
}
catch
{
// just catch and ignore with a short pause...
System.Threading.Thread.Sleep(5000);
}
}
}
}
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
private void WriteToEventLog(Exception ex, EventLogEntryType eventLogEntryType)
{
try
{
string message = string.Empty;
string sTrace = ex.StackTrace;
while (ex != null)
{
message = message + Environment.NewLine + Environment.NewLine + ex.Message;
ex = ex.InnerException;
}
message = message + Environment.NewLine + Environment.NewLine + sTrace;
this.EventLog.WriteEntry(message, eventLogEntryType);
}
catch (Exception ex2)
{
WriteToEventLog(ex2, EventLogEntryType.Error);
}
}
private void WriteToEventLog(string message, EventLogEntryType eventLogEntryType)
{
try
{
this.EventLog.WriteEntry(message, eventLogEntryType);
}
catch (Exception ex)
{
WriteToEventLog(ex, EventLogEntryType.Error);
}
}
#endregion
}
}
回答1:
Even though it's running as a release exe, you'll still be given the option to attach to a debugger when the app crashes... you just won't see debug symbols, just assembly :)
I believe it's the Dr. Watson process that catches app errors for debugging... Because your app is a service, Dr. Watson can't interact with the desktop, giving you the error you see. You can go to the service properties and mark "allow service to interact with the desktop", found on the LogOn tab, which should then give you a Dr. Watson popup when the app crashes.
Steps to disable Dr. Watson are here:
http://support.microsoft.com/kb/188296
If you want to debug the app on the server, you can enable remote debugging on the server, and attach Visual Studio to the process... if you want to try this, I can give you more tips for debugging a windows service remotely.
HTH, James
* Edit *
Based on the code you provided, I'd look at the following areas:
Is
AppSettings.Default.FTPRootPathset correctly inApp.Config?Are there changes happening to that directory immediately when the service starts? You have a timer commented as "check every five minutes", which is a little confusing, because the
FileSystemWatcherwill start receiving events as soon as you setEnableRaisingEventsto true. So the issue could actually lie withinfileCreatedOrChangedAlong those lines, you have one
BackgroundWorkerservicing multiple events, and worse, you're firing the handler asynchronously. This is my most likely suspect, because if you call_worker.RunWorkerAsync()again while the first job is running, you'll get anInvalidOperationException. Though I'm not sure why you wouldn't see that in the logYou're using the timer to update the last write time for all files in the watched directory, and you do this every five seconds. This seems like a very bad idea... I'm not sure what you're trying to accomplish. This will fire your
FileSystemWatcher's changed event, which would explain why you're crashing less than 10 seconds after you start (the timer's initial tick is set to fire immediately, meaning five seconds later you're changing all the file times, triggering theFileSystemWatchermultiple times shortly after that)
So my best guess is that within five seconds, you've begun firing multiple RunWorkAsync() calls on the same BackgroundWorker, which is a no-no : )
Setting the static variable _isBusy to true/false isn't reliable because you're multi-threading with the BackgroundWorkers... you need to use a Mutex or some other lock, but doesn't that really defeat the purpose of using a BackgroundWorker?
Also, if you wanted to use something like an isBusy flag, it would have to look more like:
while (_isBusy) {
System.Threading.Thread.Sleep(5000);
}
_isBusy = true;
_worker.RunWorkerAsync(eventArgs);
You need _isBusy to be false before you try to launch the Background worker... the way you have it, if the event fires 100 times, you'll make 100 calls.
The easiest solution to your problem would be to create a new BackgroundWorker in the fileCreatedOrChanged method every time the event fires... there's overhead involved in creating so many new threads, but if the work being done in this method is significant, it will be worth the overhead.
You might be able to rely on the built-in BackgroundWorker.IsBusy property, but again, I'd have to question the benefit of asynchronous threading if you're just going to block until the background worker completes.
** Edit **
I understand now what you're trying to accomplish with the initial file timestamp changes... I think you would do better to leave the timestamps alone, but just run through a startup loop to process existing files. You can spawn a background worker thread for each one, just like you do on the FileSystemWatcher nofications. The way you're handling it is deliberately creating a side-effect to trigger the result you want.
I'm losing track a little bit in the growing complexity... the whole queue/dequeue thing might be unnecessary. Or maybe I just am not seeing a need that is truly there. Again, what strikes me is that you are launching the background worker asynchronously, then putting the main thread to sleep until it finishes.
When you put the main thread to sleep, no events will get processed, so you are truly throttling the multi-threading to one thread. I see that you want to write to the event log how long it took for a thread to finish. I will start a second answer to address that if I get a chance to, but the gist of it is to pass a Stopwatch class (which will give you an accurate count of either milliseconds or CPU ticks that pass during an operation) to the DoWorkEventArgs.Result property.
But the code you requested! Basically, wherever you decide to call _worker.RunWorkerAsync(queuedFile), rather than run one class-level BackgroundWorker create a new one each time. Pass all the same parameters for the event handlers, etc. Your service entry point would drop all the BGW references and look like:
protected override void OnStart(string[] args)
{
try
{
_keys.AddRange(new string[] { "csv", "xml", "zip", "rivx" });
_watcher = new FileSystemWatcher(AppSettings.Default.FTPRootPath, "*.*");
_watcher.IncludeSubdirectories = true;
_watcher.NotifyFilter = sysIO.NotifyFilters.DirectoryName | sysIO.NotifyFilters.FileName | sysIO.NotifyFilters.LastAccess | sysIO.NotifyFilters.CreationTime | sysIO.NotifyFilters.LastWrite;
_watcher.Created += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.Changed += new sysIO.FileSystemEventHandler(fileCreatedOrChanged);
_watcher.EnableRaisingEvents = true;
WriteToEventLog("Exit Start", EventLogEntryType.Information);
}
and the code where you run the BGW asynchronously would become:
BackgroundWorker worker = new BackgroundWorker();
worker.WorkerReportsProgress = true;
worker.WorkerSupportsCancellation = true;
worker.DoWork += new DoWorkEventHandler(BackgroundWorkerDoWork);
worker.ProgressChanged += BackgroundWorkerProgressChanged; // Note you don't need
worker.RunWorkerCompleted += BackgroundWorkerRunWorkerCompleted; // the 'new' here
worker.RunWorkerAsync(queuedFile); // goes to BackgroundWorkerDoWork(object sender, DoWorkEventArgs e) //
回答2:
The error message tells you that it couldn't attach a debugger to let you inspect the exception. This is completely unrelated to the fact that this is a release build. Release build and debug builds can both be debugged (fortunately!).
Debugging services is a little different from debugging regular applications. Please check this guide for some advice.
来源：https://stackoverflow.com/questions/3979946/c-sharp-based-windows-service-tries-to-do-jit-debugging-in-production