FIX: Connection leak with .NET Data Provider for Oracle in ASP.NET (330126)


The information in this article applies to:

  • Microsoft .NET Framework 1.0 SP2
This article was previously published under Q330126

SYMPTOMS

When you use the Microsoft .NET Framework Data Provider for Oracle inside ASP.NET, over time, the number of connections to the Oracle database increases beyond what you expect. Additionally, you detect an increasing number of idle connections when you examine Oracle connections on the Oracle server.

RESOLUTION

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Microsoft .NET Framework service pack that contains this fix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later:
   Date        Version     Size     File name
   -------------------------------------------------------------
   18-Oct-2002 1.0.1087.0  290,816  System.data.oracleclient.dll

WORKAROUND

You can release the Oracle connections by restarting the IIS Admin service and all IIS dependant services and processes (such as dllhost.exe, and aspnet_wp.exe).

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

When ASP.NET recycles an AppDomain, the finalizers for the .NET Framework Data Provider for Oracle do not correctly clean the native connections to the Oracle server. Over time, when an AppDomain in ASP.NET is cycled over and over, the number of native Oracle connections increases. When you restart IIS, all dependant processes recycle. When you close these processes, the native TCP/IP socket handles are released. This hotfix resolves this problem by correctly cleaning the native Oracle connections in the finalizers.

This issue occurs most frequently in ASP.NET applications because ASP.NET can recycle the application domain in a process periodically. However, any process that creates and destroys .NET application domains may also experience this problem. Therefore, this issue is not strictly limited to ASP.NET applications.

An Oracle administrator can run the following SQL statement from the SQL*Plus utility, or another utility that can connect to Oracle and run SQL statements, to view all active and idle Oracle connections:

SELECT LOGON_TIME, OSUSER, PROCESS,MACHINE,PROGRAM 
FROM V$SESSION WHERE PROGRAM IS NOT NULL
This displays a list of all computers and processes that are connected to the Oracle database. The list includes the names of the processes that opened the connections. The following is an example of this list:
LOGON_TIME          OSUSER PROCESS      MACHINE            PROGRAM
------------------- ------ ------- ------------------ ------------
2002-08-30 14:31:01 ASPNET 832:177 MYDOMAIN\MYMACHINE aspnet_wp.exe
2002-08-30 14:31:01 ASPNET 832:176 MYDOMAIN\MYMACHINE aspnet_wp.exe
Note
  • LOGON_TIME. The time when the connection was opened.
  • OSUSER. The operating system of the user who opened the connection.
  • PROCESS. The process id and thread id where the connection was first opened.
  • MACHINE. The domain and machine name where the process resides.
  • PROGRAM. The executable name that created the connection.
You can use the LOGON_TIME to search for possible long-running idle connections.
Modification Type:MajorLast Reviewed:4/7/2006
Keywords:kbQFE KBHotfixServer kbbug kbfix kbOracle kbSystemData KB330126 kbAudDeveloper
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