In the late 90's, I worked on porting a FORTRAN reactor simulator to Windows 95/NT/XP. On the order of 30 MLoC for an industry/research joint project that was a

In the late 90's, I worked on porting a FORTRAN reactor simulator to Windows 95/NT/XP. On the order of 30 MLoC for an industry/research joint project that was around 40 years old at the time. It took a long time to compile, but even longer to run. It turned out that disabling swap on Windows was the single biggest runtime performance improvement on machines with around 128-258 MiB of RAM. Windows would cheerfully page out the working set when there was no other non-system source of memory pressure. PS: The time for SMRs was 40 years ago. Renewables radically transformed the economics such that only fusion reactors, geothermal, and tidal are part of a short list of viable alternatives because fossil fuels and fission need to go the way of whale oil and hunting passenger pigeons.