"Initial Memory Percentage" registry value has no effect

When the Initial Memory Percentage registry value is put in place to change the default memory allocation that is used for the Exchmem heaps, the initial memory heap size that is used by Exchange 2000 Server may not change.

This problem occurs because of an issue in the code for the Exchmem component that ignores the Initial Memory Percentage registry setting.

Cumulative Patch Information

To resolve this problem, obtain the March 2003 Exchange 2000 Server Post-Service Pack 3 (SP3) Rollup. For additional information about how to do so, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfix Information

A supported hotfix is 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.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if 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. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language. The Global version of this fix has the file attributes (or later) 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 has confirmed that this is a problem in Microsoft Exchange 2000 Server.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
This setting is useful when you are tuning an Exchange 2000 Server computer because of virtual memory fragmentation issues. Only use this method after the correct diagnosis has been made. Adding this value changes the amount of memory that is initially allocated for the Exchmem heaps, dropping it to 10 percent of physical memory. To do this, create the Initial Memory Percentage registry value in the following registry subkey: Value type: REG_DWORD
Value name: Initial Memory Percentage
Value data: 0xa

This reduces the default allocation to 10 percent of RAM.