How much extra memory does garbage collection require?

Question

I heard once that for a language to implement and run garbage collection correctly there is on average of 3x more memory required. I am not sure if this is assuming the

Answer 1

I hope the original author clearly marked what they regard as correct usage of garbage collection and the context of their claim.

The overhead certainly depends on many factors; e.g., the overhead is larger if you run your garbage collector less frequently; a copying garbage collector has a higher overhead than a mark and sweep collector; and it is much easier to write a garbage collector with lower overhead in a single-threaded application than in the multi-threaded world, especially for anything that moves objects around (copying and/or compacting gc).