FIX: Slow performance and garbage collection heap memory fragmentation occur in ASP.NET

In a Microsoft ASP.NET Web application, you may experience slow performance and garbage collection heap fragmentation when the following conditions are true:

• Many clients connect to the Web site at the same time.
• The clients connect to the Web site by using a slow network connection such as a dial-up modem connection.

The garbage collection heap fragmentation causes high memory use and slow performance.

This problem occurs because the response buffer cannot be moved in memory in the garbage collection heap while Microsoft Internet Information Services (IIS) writes the response to the client. Therefore, a long time may pass before the buffer can be moved in memory over a slow network connection. After the buffer is moved in memory, garbage collection can start to defragment the memory that is used by the buffer. When many clients connect to the ASP.NET Web application over a slow connection, the garbage collection heap may quickly become fragmented. Therefore, garbage collection may take longer to finish.

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Microsoft .NET Framework 1.1 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

No prerequisites are required.

Restart requirement

You do not have to restart your 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 has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

This hotfix reduces the memory that is required to service clients that connect over a slow network connection.

For more information about how to monitor ASP.NET application performance, visit the following Microsoft Developer Network (MSDN) Web site: For additional information, click the following article number to view the article in the Microsoft Knowledge Base: