MTU is larger than the FastSendDatagramThreshold

Source: Internet
Author: User

When you execute Uhd_usrp_probe.exe, you are prompted with "MTU is larger than the FastSendDatagramThreshold". Here's how to fix it:


You could see a message similar to the following on Windows machines when using the-the-support package for USRP Radio Rx or Tx System objects or blocks:

The MTU (1472) is larger than the FastSendDatagramThreshold (1024)!

This would negatively affect the transmit performance.

See the transport application notes for more detail.

Possible Solution

The Ettus Web site has a document,uhd-transport application Notes (broken Links), which describes this problem. See the MicroSoft Web site:optimizing Windows Media Services for Appendix E:registry Key for information on increasing th is setting. After you has perused these documents,follow the instructions in this section to apply the change.

  Warning incorrectly editing the registry may serverely damage your system. Before making changes to the Registry,you shuold back up any valued data on your computer.

To increase the fastsenddatagramthreshold,follow these steps:

1.Click Windows Start, Enter regedit in Search programs and files

2.using the left side navigation Windows,go to hkey_local_machine\system\currentcontrolset\services\afd\parameters\.

3.Right click on Parameters and Select New->dword (32-bit) Value.

4.Enter FastSendDatagramThreshold as the name.

5.Right click on fashsenddatagramthreshold value and select Modify.

6.Enter for Value data. Select Decimal as Base value.

7.Click OK. FastSendDatagramThreshold should now has the following settings:

8.Close the Registry Editor. A system reboot is recommended after the registry key change.


MTU is larger than the FastSendDatagramThreshold

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.