Thanks for your checks! Yes, if you put GC.gc(false) at the end of the loop then there is no overload of memory usage: on my small laptop the OS does not kill Julia, and on my Mac things do not get really slow after many runs.
My point is, shouldn’t Julia’s GC be able to detect this and run the GC more frequently so that this overload of memory and subsequent either killing by the OS or significant slow down does not occur?