TCP Chimney Offload transfers network traffic workload processing from the CPU to a network adapter that supports TCP Chimney Offload. This feature was introduced with Windows Server 2003 SP2, and it was called the Microsoft Scalable Networking Pack (SNP). Since Windows Server 2008, these features are a base part of these operating systems, so they no longer go by this name. To utilize this feature, the network adapter (and driver) must support this feature, and both the operating system and the network adapter must have this setting enabled.

This feature is not suitable for all applications. Microsoft says (at http://technet.microsoft.com/en-us/library/gg162709%28v=WS.10%29.aspx):

Because of the overhead associated with moving TCP/IP processing to the network adapter, TCP Chimney Offload offers the most benefit to applications that have long-lived connections and transfer large amounts of data. Servers that perform database replication, function as file servers, or perform backup functions are examples of computers that may benefit when you enable TCP Chimney Offload.

With the different operating systems versions, this feature is by default in different states:

Windows OS Default state of TCP Chimney Offload
Windows Server 2003 enabled
Windows Server 2008 disabled
Windows Server 2008 R2 automatic
Windows Server 2012 disabled

 

With all of these changes to the OS, which setting should we use for SQL Server? In general, for all of these operating systems, I recommend that TCP Chimney Offload be disabled – because you can see odd connectivity problems in any other state. Notice in the above quote that Microsoft says that this feature is best used for applications with long-lived connections that transfer large amounts of data – hopefully your OLTP database is performing lots of short-lived connections and they are not transferring large amounts of data (if they are, contact us… we can help you with that!). Some of the error messages that you can encounter are:

You can read the rest of this article over here.