Sounds more like a plain old stop-and-copy/two space GC... Generational would be if they built a chain of directories to represent one (like with an overlay fi

Sounds more like a plain old stop-and-copy/two space GC... Generational would be if they built a chain of directories to represent one (like with an overlay filesystem of some kind) and then periodically GC'd those at different rates, moving the persistent entries into less and less frequently scanned dirs.