Remote TCP Connection Offload and Applications

Layer 7 load balancers (L7LBs) play an important role in perrequest server selection within long-lived connections and transport-or application-layer protocol translation. However, L7LBs introduce substantial CPU and network overhead.

We present XO, which enables an L7LB to offload transport-layer and application request processing to backend servers at request granularity. XO outperforms conventional L7LBs by 27-365 % in throughput through efficient utilization of server CPU and network resources. We apply XO to two real-world applications, Ceph and nginx, improving throughput by up to 135 % and 300 %, respectively.