How to Tune Linux Kernel

Be Aware

Kernel Tuning should be the last option when setting up and configuring the Linux xNIC for performance. We expect users to validate network loss BEFORE attempting to optimize/tune the network kernel.

These settings have been found to increase packet rates and minimize packet drops. These settings are for implementing on a Linux machine running the swxtch-xNIC service.

To do this:

Open the /etc/sysctl.conf to begin editing.
Add the following lines:
```
net.core.rmem_default=26214400
net.core.rmem_max=26214400
```
Tip
The suggested kernel parameters above only optimize the receive buffer. If you need to increase the size of the send buffer, please contact support@swxtch.io.

Once the desired changes have been added to /etc/sysctl.conf, save changes and exit.
Run the following command to validate the change:
```
sudo sysctl -p
```
Example:

Run the following command to validate the rmem max.
```
sudo sysctl net.core.rmem_max
```
Example: