NFD-GC (NFD Garbage-Collector) is preferably run as a Kubernetes deployment with one replica. It makes sure that all NodeFeature and NodeResourceTopology objects have corresponding nodes and removes stale objects for non-existent nodes.
The daemon watches for Node deletion events and removes NodeFeature and NodeResourceTopology objects upon them. It also runs periodically to make sure no node delete event was missed and to remove any NodeFeature or NodeResourceTopology objects that were created without corresponding node. The default garbage collector interval is set to 1h which is the value when no -gc-interval is specified.
In Helm deployments see garbage collector parameters for altering the nfd-gc configuration.