TCPHA
From LVSKB
TCPHA (TCP HAndoff) implements an architecture for scalable content-aware request distribution in cluster-base servers. It implements Kernel layer-7 switching based on TCP Handoff protocol for the Linux operating system. Since the overhead of layer-7 switching in user-space is very high, it is good to implement it inside the kernel in order to avoid the overhead of context switching and memory copying between user-space and kernel-space. Furthermore, the responses are sent directly back to clients without passing through the dispatcher, which can greatly improve the performance of cluster.