Vista Tutorial - Chimney Offload State - Enable or Disable

**Brink**

How to Enable or Disable the Chimney Offload State in Vista

Information

This will show you how to enable or disable the TCP Chimney Offload State to offload TCP processing for a network connection from the CPU to the network adapter instead. This helps improve the processing of network data on your computer or server without the need for additional programs or any loss to manageability or security. Programs that are currently bound by network processing overhead will generally scale better when used with TCP Chimney Offload. For more information about this, see Information about the TCP Chimney Offload, Receive Side Scaling, and Network Direct Memory Access features in Windows Server 2008 and What is TCP Chimney Offload? - Windows Vista Help.

Tip

"The goal of TCP Chimney is to reduce CPU utilization and increase network throughput for long-lived TCP connections with bulk transfers and applications that pre-post buffers. Moving TCP processing tasks to hardware frees up the server's CPU for other application tasks."
Full read at: http://technet.microsoft.com/en-us/network/dd277645.aspx

NOTE

The TCP Chimney Offload State is enabled by default in Vista. It is recommended to have this enabled. You can test to see how your network connection speed works with either setting.

RELATED LINKS:

Here's How:

1. To See the Current TCP Settings -
A) Open a elevated command prompt.

B) Click on Continue in the UAC prompt.

C) In the elevated command prompt, type netsh interface tcp show global and press Enter. (See screenshot below)

2. To Enable the Chimney Offload State -
A) In the elevated command prompt, type netsh int tcp set global chimney=enabled and press Enter. (See screenshot below)

B) You will get a OK response if successful. If not, repeat step 2A.

C) Go to step 4.

3. To Disable the Chimney Offload State -
A) In the elevated command prompt, type netsh int tcp set global chimney=disable and press Enter. (See screenshot below)

B) You will get a OK response if successful. If not, repeat step 3A.

4. Repeat step 1 to verify the change.

5. Close the command prompt when done.

6. Restart the computer to apply.

That's it,
Shawn

**mansrm81** · 10-19-2008

Thanks for this tutorial Shawn.

**Brink** · 10-19-2008

You'rs welcome Mansrm81.

Shawn

**Airbot** · 12-13-2008

Shawn, I know that you say Chimney Offload and Autotuning are set to enabled and normal by default but I have done a clean install of Home Premium and Ultimate and they were both set to Chimney Offload=Disabled, Autotuning= HighlyRestricted. Could it have anything to do with your network adapter and or Router that determine the setting, as soon as you connect to your router/adapter? Or am I making no sense? lol

**Brink** · 12-14-2008

Hello Aaron,

I'm noticing more people reporting this, so it may be so. The settings in the tutorial are the normal recommended settings. You might try either way to see if you notice a difference between them.

**NormCameron** · 12-14-2008

Just read this. Nice one. Thanks mate

Norm

**Brink** · 12-14-2008

You're welcome Norm.

Shawn

**rickrode** · 12-19-2008

Hi Shawn,

I try step no. 2 of this tutorial enabling chimney offload state but I received a message "set global command failed on IPV4 the requested operation requires elevation" any help or additional info on this issue.

Rickrode

**Brink** · 12-19-2008

Hello Rickrode,

You will just need to open a elevated command prompt with administrator rights, as per step 1, instead of a normal command prompt.

Hope this helps,
Shawn

**rickrode** · 12-19-2008

Hi Shawn,

ha! ha ha ! I got an ok reply. Now, it improve my network, it such a great help.

Thanks a lot,

Rickrode

10-19-2008
mansrm81 Master Join Date: Aug 2008 Vista Ultimate 64bit SP2/ 1,863 posts	Re: Chimney Offload State - Enable or Disable Thanks for this tutorial Shawn.
My System Specs

10-19-2008
Brink Administrator Join Date: Apr 2007 Vista x64 Ultimate SP2, Windows 7 (7600) x64 25,815 posts	Re: Chimney Offload State - Enable or Disable You'rs welcome Mansrm81. Shawn
My System Specs

12-13-2008
Airbot You Will Service..Us Join Date: Nov 2008 Vista Ultimate SP2 x64 Windows 7 Ultimate x64 TECHNET 1,636 posts	Re: Chimney Offload State - Enable or Disable Shawn, I know that you say Chimney Offload and Autotuning are set to enabled and normal by default but I have done a clean install of Home Premium and Ultimate and they were both set to Chimney Offload=Disabled, Autotuning= HighlyRestricted. Could it have anything to do with your network adapter and or Router that determine the setting, as soon as you connect to your router/adapter? Or am I making no sense? lol
My System Specs

12-14-2008
Brink Administrator Join Date: Apr 2007 Vista x64 Ultimate SP2, Windows 7 (7600) x64 25,815 posts	Re: Chimney Offload State - Enable or Disable Hello Aaron, I'm noticing more people reporting this, so it may be so. The settings in the tutorial are the normal recommended settings. You might try either way to see if you notice a difference between them.
My System Specs

12-14-2008
NormCameron Master Join Date: Aug 2008 Windows 7 Ultimate 32 bit Beta, Vista Ultimate x86 1,082 posts	Re: Chimney Offload State - Enable or Disable Just read this. Nice one. Thanks mate Norm
My System Specs

12-19-2008
rickrode Member Join Date: Oct 2008 Vista Home Basic 32bit 5 posts	Re: Chimney Offload State - Enable or Disable Hi Shawn, I try step no. 2 of this tutorial enabling chimney offload state but I received a message "set global command failed on IPV4 the requested operation requires elevation" any help or additional info on this issue. Rickrode
My System Specs

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