1. Tcp Auto Tuning Windows 10

Try enabling 'experimental' mode for astronomical Auto-Tuning levels. When setting Windows Auto-Tuning level the possible settings are as follows: normal: default value, allows the receive window to grow to accommodate most conditions; disabled: uses a fixed value for the tcp receive window. Limits it to 64KB (limited at 65535). In Windows Vista, Windows Server 2008, and later versions of Windows, the Windows network stack uses a feature that is named TCP receive window autotuning level to negotiate the TCP receive window size. This feature can negotiate a defined receive window size for every TCP communication during the TCP Handshake. The operating system can configure connections by scaling the TCP receive window to maximize the network performance based on these parameters. To determine the optimal size for the receive window, the receive window autotuning feature measures the product of the network delay and bandwidth, and also looks at the application retrieve-rates.

Windows 10 have an auto-tuning feature which tries to dynamically adjust the receive buffer size for transmission and latency of the link. In-fact this feature is present in all Modern Operating systems including Windows 10. So, its a Necessary Feature all together as it manages and adjusts Receive buffer size dynamically.

How to Check if Auto Tuning Feature is Enabled ?

And the culprit was: TCP Receive Window Auto-Tuning. This feature is enabled by default on Vista, and attempts to automatically tune some TCP parameters including the Receive Window size to improve network performance. Unfortunately this can interact poorly with some pieces of network gear or firewalls leading to slowness or hangs. The Receive Window Auto-Tuning feature lets the operating system continually monitor routing conditions such as bandwidth, network delay, and application delay. Therefore, the operating system can configure connections by scaling the TCP receive window to maximize the network performance.

1 – Open Command Prompt as admin by Searching cmd in Windows 10 Search box and then right clicking on the cmd icon and clicking on Run as Administrator.

2 – Now, run the following command given below.

3 – In the output if Receive Windows Auto Tuning Level says Normal, then the Auto tuning Feature is enabled on your PC.

How to Disable Auto Tuning in Windows 10

# Using Command Prompt: –

Just run the command given below in Command Prompt

# Using Registry Editor:-

1] Press Windows key + R together.

2] Write Regedit and hit enter to Open registry editor.

3] Browse to the following location Given below.

4 ] Now, Right click anywhere on right side and create New -> DWORD (32-bit) Value

5 ] Now, Name this key TcpAutotuning .

6 ] Double click on it and Edit Value data to 0.

How to Enable Auto Tuning in Windows 10

# Using Command Prompt: –

Just run the command given below in Command Prompt

# Using Registry Editor:-

1] Press Windows key + R together.

2] Write Regedit and hit enter to Open registry editor.

3] Browse to the following location Given below.

4 ] Now, Right click anywhere on right side and create New -> DWORD (32-bit) Value if it does not exists.

6 ] Double click on it and Edit Value data to 0.

Saurav is associated with IT industry and computers for more than a decade and is writing on The Geek Page on topics revolving on windows 10 and softwares.

This article describes how the Receive Window Auto-Tuning feature improves data transfer, how to enable/diable this feature for HTTP traffic on Windows Vista-based computers, and issues that may occur after you enable this feature for HTTP traffic.

Original product version: Windows Vista
Original KB number: 947239

Introduction

Windows Vista includes the Receive Window Auto-Tuning feature that improves performance for programs that receive TCP data over a network. However, this feature is disabled by default for programs that use the Windows HTTP Services (WinHTTP) interface. Some examples of programs that use WinHTTP include Automatic Updates, Windows Update, Remote Desktop Connection, Windows Explorer (network file copy), and Sharepoint (WebDAV).

If you enable Receive Window Auto-Tuning for WinHTTP traffic, data transfers over the network may be more efficient. However, in some cases you might experience slower data transfers or loss of connectivity if your network uses an older router and firewall that does not support this feature. For example, when you use Windows Internet Explorer to access applications that are hosted in Microsoft Office SharePoint Server, the HTTP traffic may slow down. This occurs because certain routers do not support the Receive Window Auto-Tuning feature.

Note

Since the release of Windows 7, Receive Window Auto-Tuning is now available for programs that use the Windows Internet (WinINet) application programming interface (API) for HTTP requests instead of WinHTTP. Some examples of programs that use WinINet for HTTP traffic include Internet Explorer, Outlook, and Outlook Express.

How Receive Window Auto-Tuning feature improves data transfer

The Receive Window Auto-Tuning feature lets the operating system continually monitor routing conditions such as bandwidth, network delay, and application delay. Therefore, the operating system can configure connections by scaling the TCP receive window to maximize the network performance. To determine the optimal receive window size, the Receive Window Auto-Tuning feature measures the products that delay bandwidth and the application retrieve rates. Then, the Receive Window Auto-Tuning feature adapts the receive window size of the ongoing transmission to take advantage of any unused bandwidth.

Enable Receive Window Auto-Tuning feature for WinHTTP traffic

Note

Prerequisites: You must be running Windows Vista Service Pack 2 or Windows Vista Service Pack 1, or have hotfix 939006 installed to enable auto-tuning for WinHTTP.

Important

This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: 322756 How to back up and restore the registry in Windows
To enable the Receive Window Auto-Tuning feature for HTTP traffic, you must edit the registry. To do this, follow these steps:

1. Click Start, type regedit in the Start Search box, and then press ENTER.
2. Locate and then right-click the registry subkey HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionInternet SettingsWinHttp.
3. Point to New, and then click DWORD Value.
4. Type TcpAutotuning, and then press ENTER.
5. Right-click TcpAutotuning, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Exit Registry Editor.
8. Restart the computer.

The Receive Window Auto-Tuning feature is enabled for HTTP traffic if the TcpAutotuning registry entry is set to 1. The Receive Window Auto-Tuning feature is not enabled for HTTP traffic if the TcpAutotuning registry entry does not exist or if it is set to a value that is not 1.

To enable the Windows Internet (WinINet) in Windows 7, follow these steps:

1. Click Start, type regedit in the Search programs and files box, and then press ENTER.

2. Locate and then right-click the registry subkey HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionInternet Settings.

3. Point to New, and then click DWORD Value.

4. Type TcpAutotuning, and then press ENTER.

5. Right-click TcpAutotuning, and then click Modify.

6. In the Value data box, type 1, and then click OK.

7. Repeat step 2 through step 6 to add a TcpAutotuning entry with DWORD value of 1 under the following registry subkey:

   HKEY_LOCAL_MACHINESOFTWAREWow6432NodeMicrosoftWindowsCurrentVersionInternet Settings

8. Exit Registry Editor.

9. Restart the computer.

WinINet is enabled if the TcpAutotuning registry entries are set to 1. WinINet is not enabled if the TcpAutotuning registry entries do not exist or if they are set to a value that is not 1.

Check whether the problem is fixed. If the problem is fixed, you are finished with this article. If the problem is not fixed, you can contact support.

Issues that may occur after you enable the Receive Window Auto-Tuning feature for HTTP traffic

When the Receive Window Auto-Tuning feature is enabled for HTTP traffic, older routers, older firewalls, and older operating systems that are incompatible with the Receive Window Auto-Tuning feature may sometimes cause slow data transfer or a loss of connectivity. When this occurs, users may experience slow performance. Or, the applications may crash. These older devices do not comply with the RFC 1323 standard. Some device manufacturers provide software that works around the hardware limitations. Contact the device manufacturer to determine whether this kind of software is available.

If the incompatible devices are outside your organization, and you cannot change the devices, this issue will remain. Therefore, you may have to disable the Receive Window Auto-Tuning feature for HTTP traffic.

Disable the Receive Window Auto-Tuning feature

To disable the Receive Window Auto-Tuning feature for HTTP traffic, follow these steps:

1. Log on to the computer as a user who has administrative credentials.

2. Click Start, type runas /user: local_computer_name administrator cmd in the Start Search box, and then press ENTER.

3. When you are prompted for the administrator account password, type the correct password, and then press ENTER.

4. At the command prompt, type the following command, and then press ENTER:

5. Exit the Command Prompt window.

6. Restart the computer.

Tcp Auto Tuning Windows 10

Check whether the problem is fixed. If the problem is fixed, you are finished with this article. If the problem is not fixed, you can contact support.