[dvko]

Very fun challenge that nerd sniped me right away. Had to do a C version in standard C99 with POSIX threads. It[1] clocks in at just under 4 seconds on my AMD Ryzen 4800U Laptop CPU.

Should run about 10-20% faster than that on the mentioned Hetzner hardware.

- Since we only do one decimal of floating point precision it uses integer math right from the get-go.

- FNV1-a hash with linear probing and a load factor well under 0.5.

- Data file is mmap’d into memory.

- Data is processed in 8 totally separate chunks (no concurrent data structures) and then those aggregations are in turn aggregated when all threads have finished.

1: https://github.com/dannyvankooten/1brc