Work on generational GC has been proceeding in parallel with the exact rooting work. You can see what the current generational GC performance is on standard be

Work on generational GC has been proceeding in parallel with the exact rooting work. You can see what the current generational GC performance is on standard benchmarks like Octane by looking at the "Firefox (Ion, GGC)" line on http://arewefastyet.com/ http://arewefastyet.com/