[ncmncm]

The expression is "premature optimization". And, Donald Knuth.

GC overhead is always hard to measure except end-to-end, because it is distributed over everything else that happens. Cache misses, TLB shoot-downs. Mitigations are very difficult to place.

Practically, you usually just have to settle for lower performance, and most people do. Double or triple your core count and memory allocation, and bull ahead.