Single RX queue kernel bypass in Netmap for high packet rate networking

The text discusses how the Linux kernel network stack has performance limitations, especially when dealing with large packet floods. To address this issue, the author's company decided to contribute to the Netmap project. They introduced a "single RX queue mode" that allows selected network flows to be offloaded to a user space application for high-speed filtering while leaving other packets to be handled by the kernel as usual. The patch is awaiting code review and can be found on GitHub. The author also provides an example of how to run this with an Intel IXGBE NIC, demonstrating that it can handle about 5.8 million packets per second.