UHD Warning: recv Buffer Size Too Small for High-Throughput Streaming

Issue Details

When running UHD example applications, users may encounter a warning related to the receive buffer size (recv buffer size). This typically indicates that the system’s default socket buffer size is too small for high-throughput streaming applications.

Solution

To prevent the recv buffer size warning and ensure optimal performance, increase the system’s receive and transmit buffer sizes. Rather than entering the command manually each time, you can make the settings permanent by modifying your Linux configuration. To help resolve this issue, follow the steps outlined below.

Steps:

1. Open the system configuration file in a text editor:
   $ sudo nano /etc/sysctl.conf

2. Append the following lines at the end of the file:
   
   net.core.rmem_max = 250000000
   net.core.wmem_max = 250000000

3. Save and close the file.

4. Apply the changes with:
   
   $ sudo sysctl -p

These settings increase the maximum socket buffer sizes, which helps UHD applications handle high data rates without dropping packets.

Additional Information

These changes affect all applications using socket buffers, not just UHD.