FIX: You experience slow performance when the # Induced GC count is high in managed Windows Forms applications (831263)

SYMPTOMS

You experience slow performance when you use a Microsoft Windows Forms application. When you view the Performance Monitor (PerfMon) counters, you notice that the value of the following counter is high:

.NET CLR Memory - # Induced GC

Note Unless you call GC.Collect() explicitly, a typical WinForms application should have a # Induced GC count close to zero. This hotfix is applicable in the event where the counter reaches several hundred counts within a few minutes after the Windows Forms application starts up.

CAUSE

This problem may occur if the Windows Forms runtime is making extra calls to the garbage collector.

The Windows Forms runtime tracks all outstanding GDI Device Contexts. The Windows Forms runtime also has an internal mechanism to force garbage collection if the number of outstanding GDI Device Contexts is higher than a predetermined threshold. This system aggressively deletes nonessential objects when resources are scarce on some operating systems.

This behavior causes slow performance if the outstanding GDI Device Context count is not valid and the count causes the Windows Forms runtime to make extra calls to the garbage collector.

RESOLUTION

Software update information

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:

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

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.

Software update file information

The English version of this software update 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.

   Date         Time   Version      Size       File name
   --------------------------------------------------------------------
   13-Nov-2003  9:44  1.1.4322.969  2,039,808  System.Windows.Forms.dll
   13-Nov-2003  9:43  1.1.4322.969  1,703,936  System.Design.dll
   13-Nov-2003  9:38  1.1.4322.969    466,944  System.Drawing.dll

MORE INFORMATION

You can monitor the extra calls to the garbage collector by identifying an unexpected increase in the .NET CLR Memory - # Induced GC PerfMon counter.

For additional information about how to use PerfMon, click the following article number to view the article in the Microsoft Knowledge Base:

248345 How to create a log using System Monitor in Windows 2000

For additional information about the terminology that is used to describe Microsoft product updates, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates