Building `openjfx11` or `openjfx12` on a machine with many cores can consume huge amounts of RAM. With 24 cores, the memory usage exceeded `25GB` per build for me.
Using `NIX_BUILD_CORES` to reduce the number of parallel tasks doesn't help, because a script invoking `cmake` does not respect `NIX_BUILD_CORES` and passes `-j <number of cores>`.
Setting `NUMBER_OF_PROCESSORS` overrides the automatic core count detection in the script.
https://github.com/search?q=repo%3Aopenjdk%2Fjfx%20NUMBER_OF_PROCESSORS&type=code
Co-authored-by: Fabian Möller <fabianm88@gmail.com>
