5.x was the start of "Giant lock" elimination: https://lists.freebsd.org/pipermail/freebsd-hackers/2007-November/022368.html https://lists.freebsd.org/pipermail

5.x was the start of "Giant lock" elimination: https://lists.freebsd.org/pipermail/freebsd-hackers/2007-November/022368.html https://lists.freebsd.org/pipermail/freebsd-hackers/2007-Nov... There wasn't a "STABLE" release of it until FreeBSD 5.3 https://en.wikipedia.org/wiki/FreeBSD_version_history#FreeBSD_5 https://en.wikipedia.org/wiki/FreeBSD_version_history#FreeBS... FreeBSD may not be a perfectly-run project but I honestly can't imagine using anything else :)