Handle Leak in SnaBase When SNA API DLL Is Loaded/Unloaded Repeatedly

• Microsoft SNA Server, versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 3.0 SP4, 4.0, 4.0 SP1, 4.0 SP2

SYMPTOMS

An SNA Server application may experience a memory and handle leak if the application repeatedly calls LoadLibrary and FreeLibrary on the SNA API DLL interface that its using. These API interfaces include RUI (Winrui32.dll), SLI (Winsli32.dll), APPC (Wappc32.dll) and CPIC (Wcpic32.dll). In addition to the application resource leaks, this behavior will also cause the SnaBase process handle count to increase over time, as viewed by Windows NT Performance Monitor. This behavior was found by an application which repeatedly loaded and unloaded the RUI interface (Winrui32.dll).

CAUSE

When the SNA API DLL is dynamically loaded and unloaded, resource leaks occurred in the underlying Snadmod.dll, which is statically linked to the SNA API DLLs.

RESOLUTION

To resolve this problem, obtain the latest service pack for SNA Server version 4.0. For additional information, please see the following article in the Microsoft Knowledge Base:

Q215838 How to Obtain the Latest SNA Server Version 4.0 Service Pack

WORKAROUND

This problem can be avoided if the application loads the SNA API DLL only once when starting, and unloads it when exiting.

STATUS

Microsoft has confirmed this to be a problem in Microsoft SNA Server versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 3.0 SP4, 4.0, 4.0 SP1, 4.0 SP2. This problem was first corrected in SNA Server version 4.0 Service Pack 3.

Additional query words:

Keywords : sna4sp3fix sna3 sna3sp1 sna3sp2 sna3sp3 sna3sp4 sna4 sna4sp1 sna4sp2
Version : WINDOWS:3.0,3.0 SP1,3.0 SP2,3.0 SP3,3.0 SP4,4.0,4.0 SP1,4.0 SP2
Platform : WINDOWS
Issue type : kbbug