Modern GCs use multiple threads to collect garbage. Also, it is possible to design a GC that does not pause mutator (e.g. C4) or does most of the things concurr

Modern GCs use multiple threads to collect garbage. Also, it is possible to design a GC that does not pause mutator (e.g. C4) or does most of the things concurrently (CMS) or does incremental sweeps (G1 and other evacuating collectors), or uses separate isolated heaps for each thread (Erlang GC).