Microsoft KB Archive/910142

= FIX: The BizTalk Service may appear to stop responding and you may receive out-of-memory error messages in BizTalk Server 2004 =

Article ID: 910142

Article Last Modified on 11/15/2007

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APPLIES TO


 * Microsoft BizTalk Server 2004 Service Pack 1
 * Microsoft BizTalk Server 2004 Standard Edition
 * Microsoft BizTalk Server 2004 Partner Edition
 * Microsoft BizTalk Server 2004 Enterprise Edition
 * Microsoft BizTalk Server 2004 Developer Edition

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SYMPTOMS
When Microsoft BizTalk Server 2004 is installed, the BizTalk Service may appear to stop responding. Additionally, you may receive out-of-memory error messages. This problem may occur even though you have sufficient available memory for the BizTalk Server 2004 process when you review process memory in Windows Performance Monitor or in Windows Task Manager.



CAUSE
This out-of-memory problem is caused by memory fragmentation.



Hotfix information
A supported hotfix is now available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next service pack that contains this hotfix.

To resolve this problem, submit a request to Microsoft Online Customer Services to obtain the hotfix. To submit an online request to obtain the hotfix, visit the following Microsoft Web site:

http://go.microsoft.com/?linkid=6294451

Note If additional issues occur or any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. To create a separate service request, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Prerequisites
You must have BizTalk Server 2004 installed to apply this hotfix.

Restart requirement
You do not have to restart the computer after you apply this hotfix.

Hotfix replacement information
This hotfix does not replace any other hotfixes.

File information
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.Microsoft BizTalk Server 2004, x86

Note Because of file dependencies, the most recent hotfix that contains these files may also contain additional files.



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section.



MORE INFORMATION
To enable this hotfix, the operating system that is installed on the computer must support the Low Fragmentation Heap algorithm. Microsoft Windows XP and Microsoft Windows Server 2003 support the Low Fragmentation Heap algorithm.

Heap fragmentation occurs when available memory is broken into small, noncontiguous blocks. When this behavior occurs, memory allocation can fail even though sufficient memory is in the heap to satisfy the request. This problem occurs because no one block of memory is large enough to satisfy the allocation request.

For applications that have a low memory usage, the standard heap is sufficient. Allocations will not fail because of heap fragmentation. However, if the application allocates memory frequently and uses a variety of allocation sizes, memory allocation can fail because of heap fragmentation. Low fragmentation heap (LFH) is built on the existing heap. However, as the name implies, LFH reduces fragmentation of the heap.

To enable LFH in operating systems that support the Heap API, you must call the supporting HeapSetInformation API function that this change in BizTalk Server enables. For more information, visit the following Microsoft Developer Network (MSDN) Web site:

http://msdn2.microsoft.com/en-us/library/aa366750.aspx

Heap fragmentation may occur under many different circumstances in BizTalk Server. The number and the size of the documents that BizTalk Server may process is not the determining factor when you evaluate if this change will work in a particular environment. Heap fragmentation occurs in a process that is based on the allocation patterns of the process in a specific heap.

When you test BizTalk Server after fragmentation has occurred, the two heaps that typically show the most fragmentation are the Microsoft Data Access Components (MDAC) heaps and the default heap. For the default BizTalk Server heap, LFH is only enabled for this heap. No other heaps are affected. Therefore, an LFH heap may not make a change in every situation.

