Chamelio

Chamelio is a flexible network stack that lets tenants upload custom network protocols that run in a shared datapath for virtual machines. Chamelio exposes a programming interface that allows tenants to upload verifiable eBPF handlers that get registered in a fast path running on the host. The fast path enforces performance isolation by bounding the maximum number of instructions permitted in each handler and leveraging fine-grained cycle-level accounting to schedule handlers from different tenants. Furthermore, Chamelio reduces the eBPF programmability tax by combining opaque eBPF handlers and infrastructure code into the same LLVM IR to enable cross-module compiler optimizations.