"Utwig" wrote:

> Hello,
> I'm using .NET Framework 1.1, C#. A couple of days before I've found out
> that my application leaks memory not releasing objects with destructors. I'm
> using some third-party components (Spring.NET and Oracle Data Provider .NET
> (ODP.NET is actually a leak in my case)). I know that it's a good habit to
> call Dispose() if the object is IDisposable, but in my case I cannot do this,
> and need to rely on destructor (performance loss was considered).
> Then I've tried to reproduce the problem in a small test project (with only
> ODP.NET objects) and failed :(. The leak was away.
> Now I suspect that Spring.NET/ODP.NET somehow blocks the finalizer thread,
> so that it never clears the garbage left.
>
> Justification:
>
> /// <summary>
> /// Create a new session
> /// </summary>
> /// <returns>The new session that can be used by the client.</returns>
> public ISession CreateSession()
> {           
>     GC.Collect();
>     GC.WaitForPendingFinalizers(); //Application hangs here
>     GC.Collect();
>     GC.WaitForPendingFinalizers();
>
>     new Message(Message.MessageType.CalledCreateSessionOn0,
> this.GetType().FullName).LogDebug();
>
>     ISession session = (ISession)
> Application.CreateSession()[typeof(ISession).FullName+".Remote"];
>
>     return session;
> }
>
>
> This method will be called relatively early after the client starts (server
> and client interact over normal MarshalByRef objects, there is anyway not
> much interaction there...). It is practically the first client call on the
> server side. Before the first client starts there will be some Spring.NET
> initialization done and an OracleConnection opened and closed (to check that
> the database is available).
>  The problem is that this code hangs on the first call to
> GC.WaitForPendingFinalizers(). By "hangs" I mean that nothing else will be
> done in application - no log messages, in Visual Studio I can pause/stop
> application (shows me a Console.ReadLine(); line - is not relevant). I've
> been waiting for 15 minutes - no changes. The memory leak was found out by
> ANTS Profiler and is definitely there. :(
> I've also installed WinDBG in order to find out where the finalizing thread
> is blocked, but had not much advance on that field (starting from that I do
> not know which of threads is finalizing thread).
>
> I have source code for Spring.NET, but it is really huge and not quite
> understandable. I would be happy if I'll find out that the problem is really
> in Spring. Can anyone help me, please? Do I actually force the garbage
> collector in a correct manner (Collect/WaitForFinalizers,
> Collect/WaitForFinalizers)? How can I find out what the finalizing thread is
> actually doing? Does the observed behaviour (hang on
> WaitForPendingFinalizers) actually an evidence that there are problems in
> finalizer?
> Thank you in advance.