Towards Variable-Length In-Network Caching

We present StarCache, a new in-network caching architecture that can cache variable-length items to balance a wide range of key-value workloads. Unlike existing works, StarCache does not cache hot items in the switch memory. Instead, we make hot items revisit the switch data plane continuously by exploiting packet recirculation. Our approach keeps cached key-value pairs in the switch data plane while freeing them from item size limitations caused by hardware constraints. We implement a StarCache prototype on an Intel Tofino switch. Our experimental results show that StarCache can balance highly skewed workloads with various key and value sizes.