On a multiprocessor system that is running a 64-bit version of Windows Server 2003, CPU 0 approaches a 100-percent "CPU Usage" reading earlier than do other CPUs on the system (908675)

CAUSE

Although this problem may occur on smaller symmetric multiprocessing (SMP) systems, you are more likely to notice this problem in larger SMP systems that use at least four CPUs. Additionally, you are likely to notice this problem only when the system is experiencing a heavy workload, such as during performance testing.

This problem occurs only when there are at least 24 timers outstanding in the system for an extended period. Timers are used by the Windows operating system, by device drivers, and by applications that explicitly use timers or that specify timeouts in applicable system calls.

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 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.

Prerequisites

You must be running one of the following operating systems to install this hotfix:

Microsoft Windows Server 2003, Datacenter Edition for Itanium-based Systems SP1
Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems SP1
Microsoft Windows Server 2003, Datacenter x64 Edition
Microsoft Windows Server 2003, Enterprise x64 Edition
Microsoft Windows Server 2003, Standard x64 Edition

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes. However, because this hotfix replaces the Windows kernel (Ntkrnlmp.exe), this hotfix may override other previous Windows kernel replacements.

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.

Windows Server 2003, x64-based versions

File name	File version	File size	Date	Time	Platform	SP requirement	Service branch
Ntkrnlmp.exe	5.2.3790.2539	4,418,560	01-Oct-2005	03:00	x64	SP1	SP1QFE
Ntoskrnl.exe	5.2.3790.2539	4,446,208	01-Oct-2005	03:00	x64	SP1	SP1QFE

Windows Server 2003, Itanium-based versions

File name	File version	File size	Date	Time	Platform
Ntkrnlmp.exe	5.2.3790.2539	6,486,528	01-Oct-2005	03:00	IA-64

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

Technical support for Windows x64 editions

Your hardware manufacturer provides technical support and assistance for Microsoft Windows x64 editions. Your hardware manufacturer provides support because a Windows x64 edition was included with your hardware. Your hardware manufacturer might have customized the Windows x64 edition installation with unique components. Unique components might include specific device drivers or might include optional settings to maximize the performance of the hardware. Microsoft will provide reasonable-effort assistance if you need technical help with your Windows x64 edition. However, you might have to contact your manufacturer directly. Your manufacturer is best qualified to support the software that your manufacturer installed on the hardware.

For product information about Microsoft Windows XP Professional x64 Edition, visit the following Microsoft Web site:

http://www.microsoft.com/windowsxp/64bit/default.mspx

For product information about Microsoft Windows Server 2003 x64 editions, visit the following Microsoft Web site:

http://www.microsoft.com/windowsserver2003/64bit/x64/default.mspx