Microsoft KB Archive/927620

Knowledge Base

Update to enhance the throughput of applications that use Winsock Direct in a System Area Network environment in Windows Server 2003

Article ID: 927620

Article Last Modified on 10/11/2007

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APPLIES TO

• Microsoft Windows Server 2003, Datacenter Edition for Itanium-Based Systems
• Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems
• Microsoft Windows Server 2003, Datacenter x64 Edition
• Microsoft Windows Server 2003, Enterprise x64 Edition
• Microsoft Windows Server 2003, Standard x64 Edition
• Microsoft Windows Server 2003, Datacenter Edition (32-bit x86)
• Microsoft Windows Server 2003, Enterprise Edition
• Microsoft Windows Server 2003, Standard Edition (32-bit x86)
• Microsoft Windows Server 2003, Web Edition

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SYMPTOMS

When you use Microsoft Windows Server 2003 to implement Winsock Direct (WSD) in a fast System Area Network (SAN) environment, the throughput of applications that use WSD may be less than expected.

The patterns that lead to low throughput in a fast SAN environment include the following:

• Winsock applications use a combination of non-blocking sockets and overlapped operations.
• Winsock applications send a large buffer immediately after they send a small buffer.
• Winsock applications pass more than one WSABUF data structure to the WSASend API.

CAUSE

This problem occurs because of a bug in the WSD switch code.

RESOLUTION

Update information

The following files are available for download from the Microsoft Download Center:

Update for Windows Server 2003, x86-based versions

Download the 927620 package now.

Update for Windows Server 2003, x64-based versions

Download the 927620 package now.

Update for Windows Server 2003, Itanium-based versions

Download the 927620 package now.

Update information

Release Date: November 21, 2006

For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file. A supported hotfix is now 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 this specific problem. This hotfix might 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, submit a request to Microsoft Online Customer Services to obtain the hotfix. To submit an online request to obtain the hotfix, visit the following Microsoft Web site:

http://go.microsoft.com/?linkid=6294451

Note If additional issues occur or 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. To create a separate service request, visit the following Microsoft Web site:

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

Prerequisites

No prerequisites are required.

Restart requirement

You must restart the computer after you apply this hotfix.

Update replacement information

This hotfix does not replace any other updates or hotfixes.

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.

Windows Server 2003, x86-based versions

File name	File version	File size	Date	Time	Platform
Mswsock.dll	5.2.3790.2826	258,048	06-Nov-2006	08:43	x86

Windows Server 2003, x64-based versions

File name	File version	File size	Date	Time	Platform	SP requirement	Service branch
Mswsock.dll	5.2.3790.2826	491,008	05-Nov-2006	20:23	x64	SP1	SP1QFE
Wmswsock.dll	5.2.3790.2826	233,472	05-Nov-2006	20:23	x86	SP1	WOW

Windows Server 2003, Itanium-based versions

File name	File version	File size	Date	Time	Platform	SP requirement	Service branch
Mswsock.dll	5.2.3790.2826	784,384	05-Nov-2006	20:23	IA-64	SP1	SP1QFE
Wmswsock.dll	5.2.3790.2826	233,472	05-Nov-2006	20:23	x86	SP1	WOW

STATUS

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

MORE INFORMATION

This update improves both throughput and latency of the data that is sent between peer computers. 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

Keywords: kbbug kbfix kbqfe kbpubtypekc kbexpertiseadvanced kbhotfixserver kbwinserv2003presp2fix kbwinserv2003sp2fix KB927620

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