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Q279139: FIX: COM Servers Fail With Heavy Load in MTS and Windows 2000

Article: Q279139
Product(s): Microsoft FoxPro
Version(s): 6.0
Operating System(s): 
Keyword(s): kbCOMt kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet kbVS600sp5 kbVS600sp5fix
Last Modified: 27-JUL-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 6.0, on platform(s):
   - the operating system: Microsoft Windows 2000 
-------------------------------------------------------------------------------

SYMPTOMS
========

A Visual FoxPro Component Object Model (COM) server may stop responding under a
heavy load when it is run using Microsoft Transaction Server (MTS) under Windows
2000.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in the latest service pack for
Visual Studio 6.0.

For additional information about Visual Studio service packs, click the article
numbers below to view the articles in the Microsoft Knowledge Base:

  Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

  Q194295 HOWTO: Tell That a Visual Studio Service Pack Is Installed

You can download the latest Visual Studio service pack from the following
Microsoft Web site:

  Visual Studio Product Updates
  (http://msdn.microsoft.com/vstudio/downloads/updates.asp)

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Create an Active Server Pages (.asp) page named Mtstest.asp that contains the
  following code:

  <HTML>
  <BODY>
  <%
     lnsecs = Request.QueryString("delay")
     set ox = Server.CreateObject("myserver.myclass")
     response.write ox.cnt()
  %>
  </BODY>
  </HTML>

2. Place the .asp page in the Wwwroot folder on a Windows 2000 Web server.

3. On drive C, create a folder called MTSTest.

4. Start Visual FoxPro.

5. To create a table to use, run the following code:

     CREATE TABLE C:\MTSTest\Counter FREE (count i)
     INSERT INTO counter VALUES (0)
     USE
   

6. Create a project called MyServer, and add the following code to the main
  program:

  DEFINE CLASS myclass AS form OLEPUBLIC
     Datasession=2	&& private datasession
     oScriptingContext=0

     PROCEDURE Init
        SET EXCLUSIVE OFF
        USE C:\MTSTest\Counter shared
     ENDPROC
  	
     PROCEDURE xOnStartPage(p1)
     ENDPROC

     PROCEDURE MyDoCmd(cCmd)
        &cCmd	&& Just execute parameter as if it were a Fox command.
     ENDPROC

     FUNCTION MyEval(cExpr)
        RETURN &cExpr	&& Evaluate parameter as if it were a Fox expression.
     ENDFUNC

     PROCEDURE cnt(p1)
        LOCAL cStr
        REPLACE Counter.count WITH Counter.count+1
        cStr = _VFP.fullname+"<br>"
        cStr = cStr + 'thread id = '+TRANS(_VFP.threadid) + "<br>"
        cStr = cStr + 'Proc id = '+TRANS(_VFP.processid)+ "<br>"
        cStr = cStr + '<font size=5 color = red>Count = TRANS(Counter.count)+'</font><br>'
        RETURN  cStr
     ENDPROC

  ENDDEFINE

7. Build the COM server.

8. Create a package for the COM server in MTS on the Web server. (For more
  information, see the "References" section.)

9. Hit Mtstest.asp with multiple threads using the Microsoft Web Application
  Stress Tool. (For more information, see the "References" section.)

10. Look at the Web Application Stress Tool report. Failures may be listed in
  the report as well as in the Windows Event Log.

REFERENCES
==========

For additional information, click the article numbers below to view the articles
in the Microsoft Knowledge Base:

  Q231282 INFO: Stress Tools to Test Your Web Server

  Q223406 HOWTO: Create an Empty MTS Package to Add Components for ASP

(c) Microsoft Corporation 2000, All Rights Reserved. Contributions by Mark
Barnard, Microsoft Corporation.


Additional query words:

======================================================================
Keywords          : kbCOMt kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet kbVS600sp5 kbVS600sp5fix 
Technology        : kbVFPsearch kbAudDeveloper
Version           : :6.0
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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