Space efficient conservative garbage collection (with retrospective)

Both type-accurate and conservative garbage collectors have gained in importance since the original paper was written. Managing unnecessary retention by conservative collectors continues to be an important problem. There appear to be few reimplementations of the techniques we described, but significantly refined descendents of the original implementation are alive and well inside a large number of applications. There has been later work both on quantifying space retention by conservative collectors, and on theoretical bounds for such retention.