DOCUMENT:Q138389  13-JUN-2001  [sna]
TITLE   :SNA Win 3.x Client (WNAP.EXE) Hogs CPU, Affects Some Apps
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:2.0,2.1,2.11
OPER/SYS:
KEYWORDS:

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

 - Microsoft SNA Server, versions 2.0, 2.1, 2.11, on platform(s):
    - the operating system: Microsoft Windows NT 
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SYMPTOMS
========

When you run the SNA Server Windows 3.x client process (WNAP.EXE), other
CPU-intensive Windows processes do not run properly. For example, a CPU-
intensive CAD application does not update the display in a timely fashion when
WNAP is running.

CAUSE
=====

WNAP has a loop in it that is constantly calling PeekMessage(), and then
processing any message it finds. If there is a low-priority task trying to run
(e.g., something like a screen-saver), that task is shut out.


RESOLUTION
==========

WNAP.EXE and WDMOD.DLL have been modified so that it now uses GetMessage()
instead of PeekMessage() if you add the line "PeekLoop=no" is in the [WNAP]
section of WIN.INI. For example:

   [WNAP]
   PeekLoop=no

NOTE: The default is PeekLoop=yes.


STATUS
======

Microsoft has confirmed this to be a problem in SNA Server for Windows NT. This
problem was corrected in the latest SNA Server for Windows NT, 2.11 U.S. Service
Pack. For information on obtaining the Service Pack, query on the following word
in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K

KBCategory: kbnetwork kbinterop kbbug2.00 kbbug2.10 kbbug2.11
KBSubcategory: ntnetserv ntconfig

Additional query words: prodsna wnap yield 2.00 2.10 2.11

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Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch
Version           : WINDOWS:2.0,2.1,2.11
Issue type        : kbbug
Solution Type     : kbfix

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