This talks about possible generational GC. Incremeantal/generational was available many years ago with a port to the Boehm collector. I never understood reject

This talks about possible generational GC. Incremeantal/generational was available many years ago with a port to the Boehm collector. I never understood rejecting it and generally spending effort on a bespoke collector. (I don't remember whether the Ravenbrook system was available at the time, or if it was unsuitable for some reason.)