A non-paged pool memory leak occurs when you capture specific MIDI SYSEx messages in Windows XP (921401)


The information in this article applies to:

  • Microsoft Windows XP Home Edition
  • Microsoft Windows XP Professional

SYMPTOMS

When you use a program to capture specific Musical Instrument Digital Interface (MIDI) SYSEx messages on a Microsoft Windows XP-based computer, the computer may gradually become less responsive. Eventually, the computer may stop responding.

CAUSE

This problem occurs because a leak occurs in the system non-paged memory pool. Non-paged kernel mode memory usage may increase until the memory is exhausted. If you analyze the non-paged pool tags, you can see that MXF is the largest consumer of non-paged pool. The MXF pool tag is the tag for the DirectMusic pool, or the "MIDI Transform Filter."

RESOLUTION

Hotfix 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 Windows XP 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.

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 item in Control Panel.
File nameFile versionFile sizeDateTimePlatform
Portcls.sys5.1.2600.2950146,04812-Jul-200613:50x86

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

MORE INFORMATION

For more information, 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

Modification Type:MajorLast Reviewed:7/21/2006
Keywords:kbWinXPsp3fix kbWinXPpreSP3fix kbBug kbExpertiseBeginner KB921401 kbAudEndUser
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