Invalid "Avg. Disk sec/Transfer" value returned by the RegQueryValueEx function in Windows Server 2008 or in Windows Vista

Consider the following scenario:

• You have a computer that is running Windows Server 2008 or Windows Vista.
• You query the value of the Avg. Disk sec/Transfer performance counter by using the RegQueryValueEx function.

In this scenario, the function may return a large invalid value.

Notes

• This issue does not occur if you collect the value of the same performance counter by using the Performance Monitor utility.
• This issue may occur if an application or service uses the sample code that is described on the following Microsoft Developer Network (MSDN) website:
  
  How to retrieve counter data

  (http://msdn.microsoft.com/library/aa373178(v=VS.85).aspx)
  For example, you use Microsoft System Center Operations Manager 2007 to monitor the health status of a computer that is running Windows Server 2008. In this scenario, you may receive the wrong alters for troubleshooting.

This issue occurs because of an error in the volume manager driver (Volmgr.sys).

Some applications or services close the handle to the HKEY_PERFORMANCE_DATA registry key after the RegQueryValueEx function is called. The kernel provider enables or disables the disk counter intermittently. However, the time stamps of some I/O request packets (IRPs) are not recorded when the disk counter is disabled. Therefore, the function calculates and returns some invalid data that does not have a time stamp.

Note In Windows Server 2008 or in Windows Vista, the disk counter in the kernel provider can be dynamically enabled or disabled. If the handle to the HKEY_PERFORMANCE_DATA registry key is closed, the kernel provider disables the I/O performance trace.

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 the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

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, contact 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.

Prerequisites

To apply this hotfix, you must be running Windows Vista Service Pack 2 (SP2) or Windows Server 2008 Service Pack 2 (SP2).

For more information about how to obtain a Windows Vista service pack, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to obtain a Windows Server 2008 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

Registry information

To use the hotfix in this package, you do not have to make any changes to the registry.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

File information

The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows Vista and Windows Server 2008 file information notes

Important Windows Vista hotfixes and Windows Server 2008 hotfixes are included in the same packages. However, only "Windows Vista" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows Vista" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.

• The files that apply to a specific product, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
  Collapse this tableExpand this table

  Version	Product	SR_Level	Service branch
  6.0.600 2 . 22xxx	Windows Vista and Windows Server 2008	SP2	LDR

• The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 and for Windows Vista" section. MUM files and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.

For all supported x86-based versions of Windows Server 2008 and of Windows Vista

For all supported x64-based versions of Windows Server 2008 and of Windows Vista

For all supported IA-64-based versions of Windows Server 2008

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

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: For more information about the RegQueryValueEx function, visit the following Microsoft Developer Network (MSDN) website:
For more information about how to retrieve counter data, visit the following MSDN website:
For more information about a similar issue in Windows 7 or in Windows Server 2008 R2, click the following article number to view the article in the Microsoft Knowledge Base:

Additional file information

Additional file information for Windows Vista and for Windows Server 2008

Additional files for all supported x86-based versions of Windows Vista and of Windows Server 2008

Additional files for all supported x64-based versions of Windows Vista and of Windows Server 2008

Additional files for all supported IA-64-based versions of Windows Server 2008