FIX: Unable to Change MTS Thread Pool Size (250452)


The information in this article applies to:

  • Microsoft Transaction Server 2.0
This article was previously published under Q250452
IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

You cannot adjust the thread pool size in Microsoft Transaction Server (MTS); it is fixed at 100.

CAUSE

Prior to Windows NT Server Service Pack 4, the thread pool size was fixed at 100.

RESOLUTION

To resolve this problem, install Windows NT Server Service Pack 4 or later and then adjust the thread pool size with a registry entry as described in the "More Information" section of this article.

STATUS

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

This bug was corrected in Windows NT Server Service Pack 4.

MORE INFORMATION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.


After you have applied Windows NT Server Service Pack 4, you can specify the number of threads by adding a REG_DWORD named value, ThreadPoolMax, to the package key:

HKLM/Software/Microsoft/Transaction Server/Package/{Your package GUID}

Valid values are: 0 to 0x7FFFFFFF.


Steps to Adjust the Thread Pool Size

To adjust the thread pool size using Regedt32.exe:
  1. Install Windows NT Server Service Pack 4 or later. (For information and to download Windows NT Server Service Packs, please see the "References" section of this article.)
  2. Start Registry Editor (Regedt32.exe).
  3. Locate the following key in the registry:

    HKEY_LOCAL_Machine/Software/Microsoft/Transaction Server/Packages/{Your package GUID}

  4. On the Edit menu, click Add Value, and then add the following registry value: 
       Value Name: ThreadPoolMax
   Data Type:  REG-DWORD
   Value:      0 to 0x7FFFFFFF
  5. Quit Registry Editor.

REFERENCES

For information and to download Windows NT Server Service Packs, please see the following Web site:

Microsoft Windows NT Server Downloads

Modification Type:MajorLast Reviewed:6/11/2002
Keywords:kbBug kbDSupport kbOSWinNT400sp4fix kbPerformance KB250452
©2002 Microsoft Corporation. All rights reserved.