TCP/IP Autotuning

Hi Experts,

I wanted to know how to find out if a PC has TCP Auto tuning turned on or off?

I know that this can be disabled/enabled via CMD in Windows 7 and have the commands

but lets say I want to know if a PC has it or not

Also another question is what exactly does TCP autotuning do?

to my knowledge TCP autotuning is integrated in win7 to help with transporting IP Packets (wrong terminology probably)

all suggestions welcome, thanks

Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Rob WilliamsCommented:
To answer part 1, the following will display the current autotuning level status
netsh interface tcp show global

If you are checking a remote PC on the LAN you can use Microsoft's PSexec
psexec \\PCname  netsh interface tcp show global

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
peggiegregAuthor Commented:
Thanks rob that's perfect.

I found the answer to part 2 form this site -

good article!
Rob WilliamsCommented:
Thank you peggiegreg.

More 'food for thought'.

You didn't mention why you were asking.  If it is relating to file access performance from a server there are a couple of other "tweaks" you may want to look at.  Sometimes autotuning and the others drastically affect performance, positively or negatively, sometimes they make no difference.  Newer PC and server versions as well as newer NIC drivers seem to make better use of these features but I find in many cases disabling autotuning, RSS, and Task Offloading make a huge difference.  Make note of any changes implemented, if no improvement you can always revert back.  PC, server NIC, and if a VM the host, may require changes.

From and earlier post of mine:
There are some known issues with newer advanced NIC properties such as "Task Offloading", and “Receive-Side Scaling” which drastically affect performance and stability of file share access if enabled and especially if you are running older drivers. The following outline  changing for the command line but I have found in some cases you have to do so within the advanced NIC properties for them to take effect. Any of these changes require a reboot to take effect.

To disable Receive-Side Scaling, at a command prompt, with elevated privileges, run the the following command:
netsh int tcp set global rss=disabled

To disable Task Offload, at a command prompt, with elevated privileges, run the the following command:
netsh int ip set global taskoffload=disabled

To disable Add-On Congestion Control Provider, at a command prompt, with elevated privileges, run the the following command:
netsh int tcp set global congestion=none

For more information Information about the TCP Chimney Offload, Receive Side Scaling, and Network Direct Memory Access features in Windows Server 2008

Related blog articles:
peggiegregAuthor Commented:
Hi Rob,

I was asking the question because I used to work for a company that was adamant to put disable this on all PC's going out new. I sort of understood what it was about but the main thing that I got stuck with is working out why Microsoft would enable features that should really be disabled in most instances for best performance. along with some curiosity as to what they actually do and how it operates.

what you have written above is helpful and I have taken all those commands and saved them!

Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
Switching off the TCP features was recommended with Vista and W2008, but is no longer since W7 and W2008R2.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.