1e8: parallel, 32 cores (File::Map, pack, unpack): https://www.perlmonks.org/?node_id=11115544 https://www.perlmonks.org/?node_id=11115780 Laurent + updates 3.474s iM71 + updates 2.701s Step counting in C 1.654s 1e8: parallel, 16 cores Laurent + updates 6.219s iM71 + updates 4.787s Step counting in C 2.793s 1e8: parallel, 8 cores Laurent + updates 12.061s iM71 + updates 9.200s Step counting in C 5.258s 1e8: parallel, 4 cores Laurent + updates 23.615s iM71 + updates 17.935s Step counting in C 10.056s 1e8: parallel, 2 cores Laurent + updates 46.146s iM71 + updates 34.342s Step counting in C 19.084s 1e8: non-parallel (Array): https://www.perlmonks.org/?node_id=11115841 Laurent + updates 53.961s iM71 + updates 48.673s Step counting in C 19.023s