RedLeaf: Isolation and Communication in a Safe Operating System

RedLeaf is a new operating system developed from scratch in Rust to explore the impact of language safety on operating system organization. In contrast to commodity systems, RedLeaf does not rely on hardware address spaces for isolation and instead uses only type and memory safety of the Rust language. Departure from costly hardware isolation mechanisms allows us to explore the design space of systems that embrace lightweight fine-grained isolation. We develop a new abstraction of a lightweight language-based isolation domain that provides a unit of information hiding and fault isolation. Domains can be dynamically loaded and cleanly terminated, i.e., errors in one domain do not affect the execution of other domains. Building on RedLeaf isolation mechanisms, we demonstrate the possibility to implement end-to-end zero-copy, fault isolation, and transparent recovery of device drivers. To evaluate the practicality of RedLeaf abstractions, we implement Rv6, a POSIX-subset operating system as a collection of RedLeaf domains. Finally, to demonstrate that Rust and fine-grained isolation are practical—we develop efficient versions of a 10Gbps Intel ixgbe network and NVMe solid-state disk device drivers that match the performance of the fastest DPDK and SPDK equivalents.