Why we use the Linux kernel's TCP stack

The use of the Linux kernel's TCP stack is a subject of interest due to its ability to handle multiple network applications and provide hardware independence and easy-to-use APIs. However, some argue for using a userspace network stack for better performance and lower latency. At CloudFlare, they use a "partial kernel bypass" technique to offload their anti-DDoS iptables to a very fast userspace process, saving Linux from processing attack packets and avoiding IRQ storms situations. Despite the potential benefits of kernel bypass, it is unlikely to become mainstream due to the lack of stable open-source partial kernel bypass technology and the rich ecosystem provided by the Linux TCP stack.