User-mode Programs Cannot Allocate Blocks of Virtual Memory

ID: Q216540

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/

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://www.microsoft.com/support/supportnet/overview/overview.asp

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 : nt4sp5fix
Version : winnt:4.0
Platform : winnt
Issue type : kbbug