Symptoms

You run Internet Information Services (IIS) 7.0 on a computer that is running Windows Vista or Windows Server 2008. The computer has more than 64 GB RAM. Unexpectedly, the W3wp.exe IIS process consumes 100% of CPU resources. Therefore, the computer experiences low performance.

Cause

This problem occurs because the highest memory address of the kernel mode HTTP driver (Http.sys) is defined as 64GB.

Resolution

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:

http://support.microsoft.com/contactus/?ws=supportNote 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, your computer must be running one of the following Windows operating systems:

  • Windows Vista Service Pack 1 (SP1)

  • Windows Vista Service Pack 2 (SP2)

  • Windows Server 2008

  • 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:

935791 How to obtain the latest Windows Vista service packFor 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:

968849 How to obtain the latest service pack for Windows Server 2008

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

Installation instructions

File information

The English (United States) 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.

    Version

    Product

    SR_Level

    Service branch

    6.0.600 1. 22xxx

    Windows Vista and Windows Server 2008

    SP1

    LDR

    6.0.600 2. 22xxx

    Windows Vista and Windows Server 2008

    SP2

    LDR

  • Service Pack 1 is integrated into the release version of Windows Server 2008. Therefore, RTM milestone files apply only to Windows Vista. RTM milestone files have a 6.0.0000.xxxxxx version number.

  • 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 and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintaining the state of the updated component. 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

File name

File version

File size

Date

Time

Platform

Httpapi.dll

6.0.6001.22564

31,232

16-Nov-2009

14:09

x86

Httpapi.dll

6.0.6002.22268

30,720

16-Nov-2009

14:00

x86

Http.sys

6.0.6001.22564

411,136

16-Nov-2009

12:06

x86

Http.sys

6.0.6002.22268

411,648

16-Nov-2009

11:59

x86

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

File name

File version

File size

Date

Time

Platform

Httpapi.dll

6.0.6001.22564

33,792

16-Nov-2009

14:46

x64

Httpapi.dll

6.0.6002.22268

33,792

16-Nov-2009

13:58

x64

Http.sys

6.0.6001.22564

609,792

16-Nov-2009

12:31

x64

Http.sys

6.0.6002.22268

620,032

16-Nov-2009

12:14

x64

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

File name

File version

File size

Date

Time

Platform

Httpapi.dll

6.0.6001.22564

70,656

16-Nov-2009

16:31

IA-64

Httpapi.dll

6.0.6002.22268

70,656

16-Nov-2009

13:52

IA-64

Http.sys

6.0.6001.22564

1,176,576

16-Nov-2009

12:23

IA-64

Http.sys

6.0.6002.22268

1,176,576

16-Nov-2009

12:16

IA-64

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 about software update terminology, 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

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

File name

File version

File size

Date

Time

Platform

Package_for_kb975798_client_1~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,367

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_client_2~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,969

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_client~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,713

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc_0~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,421

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc_1~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,966

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,701

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_0~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,425

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_1~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,969

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,713

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv_0~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,422

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv~31bf3856ad364e35~x86~~6.0.1.0.mum

Not Applicable

1,430

17-Nov-2009

08:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6001.22564_none_f5f90302b6967b3b.manifest

Not Applicable

4,708

16-Nov-2009

17:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22268_none_f7e37612b3b935bb.manifest

Not Applicable

4,708

16-Nov-2009

16:00

Not Applicable

X86_microsoft-windows-http_31bf3856ad364e35_6.0.6001.22564_none_ad0dc24c32258e80.manifest

Not Applicable

144,304

16-Nov-2009

17:36

Not Applicable

X86_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22268_none_aef8355c2f484900.manifest

Not Applicable

144,703

16-Nov-2009

16:02

Not Applicable

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

File name

File version

File size

Date

Time

Platform

Amd64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6001.22564_none_52179e866ef3ec71.manifest

Not Applicable

4,722

16-Nov-2009

18:59

Not Applicable

Amd64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22268_none_540211966c16a6f1.manifest

Not Applicable

4,722

16-Nov-2009

18:41

Not Applicable

Amd64_microsoft-windows-http_31bf3856ad364e35_6.0.6001.22564_none_092c5dcfea82ffb6.manifest

Not Applicable

144,568

16-Nov-2009

19:01

Not Applicable

Amd64_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22268_none_0b16d0dfe7a5ba36.manifest

Not Applicable

144,967

16-Nov-2009

18:43

Not Applicable

Package_for_kb975798_client_1~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,375

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_client_2~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,983

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_client~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,723

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc_0~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,429

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc_1~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,980

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,711

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_0~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,433

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_1~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,983

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,723

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv_0~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,430

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv~31bf3856ad364e35~amd64~~6.0.1.0.mum

Not Applicable

1,438

17-Nov-2009

08:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6001.22564_none_f5f90302b6967b3b.manifest

Not Applicable

4,708

16-Nov-2009

17:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22268_none_f7e37612b3b935bb.manifest

Not Applicable

4,708

16-Nov-2009

16:00

Not Applicable

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

File name

File version

File size

Date

Time

Platform

Ia64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6001.22564_none_f5faa6f8b6948437.manifest

Not Applicable

4,715

17-Nov-2009

02:12

Not Applicable

Ia64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22268_none_f7e51a08b3b73eb7.manifest

Not Applicable

4,715

16-Nov-2009

15:17

Not Applicable

Ia64_microsoft-windows-http_31bf3856ad364e35_6.0.6001.22564_none_ad0f66423223977c.manifest

Not Applicable

144,558

17-Nov-2009

02:14

Not Applicable

Ia64_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22268_none_aef9d9522f4651fc.manifest

Not Applicable

144,957

16-Nov-2009

15:18

Not Applicable

Package_for_kb975798_sc_0~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,425

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc_1~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,806

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_sc~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,706

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_0~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,429

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server_1~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,809

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_server~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,718

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv_0~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,426

17-Nov-2009

08:34

Not Applicable

Package_for_kb975798_winpesrv~31bf3856ad364e35~ia64~~6.0.1.0.mum

Not Applicable

1,434

17-Nov-2009

08:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6001.22564_none_f5f90302b6967b3b.manifest

Not Applicable

4,708

16-Nov-2009

17:34

Not Applicable

X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22268_none_f7e37612b3b935bb.manifest

Not Applicable

4,708

16-Nov-2009

16:00

Not Applicable

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