Directhosting Affects Powerbuilder Query Performance (152453)


The information in this article applies to:

  • Microsoft Windows NT Workstation 3.51
  • Microsoft Windows NT Server 3.51
  • Microsoft Windows for Workgroups 3.11
  • Microsoft Windows 95
This article was previously published under Q152453

SYMPTOMS

Powerbuilder client server applications that utilize the IPX/SPX Compatible Protocol (NWLINK) running under Windows for Workgroups or Windows 95 may experience a performance problem. The query from this client against SQL Server running under Windows NT may take a long time to process. Other similar types of applications may encounter the same problem.

CAUSE

Because the DIRECTHOST feature only supports half-duplex communication (only one command outstanding on the IPX session at a time), this feature causes a decrease in perfomance with network applications that use named pipes to connect.

RESOLUTION

Disable the DIRECTHOST feature.

Steps to disable the feature in Windows for Workgroups:
  1. Open System.ini.
  2. Goto the [NETWORK] section.
  3. Add a line: DIRECTHOST=NO
This change will take effect when you next start Windows for Workgroups.

Steps to disable the feature in Windows 95:

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows 95. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.
  1. Click the Start button, then click Run. The Run dialog box appears.
  2. Type "regedit" and choose OK. Registry Editor starts.
  3. Open (click on the + next to) HKEY_LOCAL_MACHINE, the go to the following subkey: 

       System\CurrentControlSet\Services\Vxd
  4. Open (click on the + next to) HKEY_LOCAL_MACHINE, then open System, CurrentControlSet, Services, and then finally open VxD.
  5. Select VNETSUP.
  6. On the Edit menu, select New, then choose String Value. A new value appears in the right-hand pane.
  7. If necessary, right click on the new item and choose Rename from the context menu. Type DirectHost and press ENTER.
  8. Right click on DirectHost and choose Modify. The Edit String dialog appears.
  9. Type 0 (zero) and click OK.
  10. Click Registry, then Exit to end the Registry Editor.
This change will take effect when you next start Windows 95
Modification Type:MajorLast Reviewed:12/16/2003
Keywords:KB152453
©2003 Microsoft Corporation. All rights reserved.