An update is available that adds support for Ethernet-based RDMA capabilities in Windows Server 2003 (924286)

RESOLUTION

Update 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 Server 2003 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.

Registry information

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

Note This registry key should only be modified by vendors who are developing Storage Area Network Providers for Winsock Direct. End users who modify these registry keys do so at their own risk. Behavior of the system is nondeterministic if end users modify this registry setting.

After you apply this hotfix, you can customize the number of send and receive buffers for Remote Direct Memory Access (RDMA) hardware. To do this, follow these steps:

In the following registry subkey, add a subkey that specifies the GUID of the service provider:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Winsock\Parameters\TCP on SAN
Note To maintain backward compatibility, retain any other subkeys in the TCP on SAN subkey.
In the new subkey, configure two registry entries:
Name Value type Value data (decimal)
SendBuffers REG_DWORD A value between 5 and 255
ReceiveBuffers REG_DWORD A value between 6 and 255
Note When these entries are not present, there are five send buffers and six receive buffers for RDMA hardware. These values are the minimum values that can be configured for these buffers. You can configure up to 255 buffers of each type. Configure these buffers to obtain the best performance relative to the hardware's throughput and latency.

Prerequisites

To apply this update, your computer must be running one of the following operating systems:

A 32-bit version of Windows Server 2003 with Service Pack 1 (SP1)
An Itanium-based version of Windows Server 2003 with SP1
An x64-based version of Windows

Restart requirement

You must restart your computer after you apply this update.

Hotfix replacement information

This update does not replace any other updates.

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	5.2.3790.2778	257,536	25-Aug-2006	17:39	x86

Windows Server 2003, x64-based versions

File name	File version	File size	Date	Time	Platform	SP requirement	Service branch
Mswsock.dll	5.2.3790.2778	489,984	27-Aug-2006	09:19	x64	SP1	SP1QFE
Wmswsock.dll	5.2.3790.2778	232,960	27-Aug-2006	09:19	x86	SP1	WOW

Windows Server 2003, Itanium-based versions

File name	File version	File size	Date	Time	Platform	SP requirement	Service branch
Mswsock.dll	5.2.3790.2778	782,848	27-Aug-2006	09:19	IA-64	SP1	SP1QFE
Wmswsock.dll	5.2.3790.2778	232,960	27-Aug-2006	09:19	x86	SP1	WOW

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 x64-based versions of Microsoft Windows

If your hardware came with a Microsoft Windows x64 edition already installed, your hardware manufacturer provides technical support and assistance for the Windows x64 edition. In this case, 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 by using 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 a 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. If you purchased a Windows x64 edition such as a Microsoft Windows Server 2003 x64 edition separately, contact Microsoft for technical support.

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 x64-based versions of Microsoft Windows Server 2003, visit the following Microsoft Web site:

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