I do know about it, I was trying to find out what difference do the parent mean between Go’s byte arrays and Java’s solution(s).

Also, I fail to get your conclusion — direct buffers only have a higher cost for initialization/dealloc otherwise reading/writing should be as cheap as it gets. Byte buffers on the other hand do get write barriers but that is also unlikely to be hit that often (and I believe larger byte arrays get allocated in a separate region that doesn’t get moved).