KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q216540: User-mode Programs Cannot Allocate Blocks of Virtual Memory

Article: Q216540
Product(s): Microsoft Windows NT
Version(s): winnt:4.0
Operating System(s): 
Keyword(s): kbWinNT400sp5fix
Last Modified: 16-MAY-2002

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

- Microsoft Windows NT Server version 4.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

User-mode programs are unable to allocate blocks of virtual memory (calls to
VirtualAlloc() do not succeed). This may result in the inability to create
threads, mutexes, critical sections, and so on.


CAUSE
=====

This problem occurs when a VirtualAlloc() critical section object is being
called to initialize part of the structure (DebugInfo). VirtualAlloc() reserves
virtual memory on a 64 KB boundary. However, this structure only allocates 4 KB
(reserve and commit) blocks of virtual memory, thereby leaving 60 KB unused.
Over time, this results in fragmentation of virtual memory and may reduce the
size of contiguous blocks available to user-mode programs.

RESOLUTION
==========

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or
the individual software update. For information on obtaining the latest service
pack, please go to:

- http://www.microsoft.com/windows/servicepacks/

-or-

- Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

For information on obtaining the individual software update, contact Microsoft
Product Support Services. For a complete list of Microsoft Product Support
Services phone numbers and information on support costs, please go to the
following address on the World Wide Web:

  http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS


STATUS
======

Microsoft has confirmed this to be a problem in Windows NT 4.0. This problem was
first corrected in Windows NT 4.0 Service Pack 5.


Additional query words: critsec

======================================================================
Keywords          : kbWinNT400sp5fix 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0
Hardware          : ALPHA x86
Issue type        : kbbug
Solution Type     : kbfix

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

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.