Read-Copy-Update
A synchronization technique that lets readers proceed with minimal coordination while updates publish a new version and defer reclamation of the old one.
Concurrency Context
Read-copy-update (RCU) is designed for read-mostly structures. An updater publishes a new version and defers reclamation of the old object until a grace period confirms that pre-existing readers have completed. Linux uses RCU extensively where very cheap read-side access is valuable.
Correctness Boundary
RCU is not a drop-in replacement for a general-purpose mutex. Update semantics, grace-period detection, and deferred memory reclamation are part of the design and can be more complex than the read path suggests.