FreeBSD’s networking stack is explicitly described as efficient, low‑latency, and designed for reduced CPU overhead, thanks to features like zero‑copy sockets and a tightly integrated TCP/IP stack. hamradio.my

Linux, by contrast, is optimized for flexibility and modularity (use on toaster, fridge, supercomputer) which can introduce overhead unless tuned. hamradio.my

BSD was probably already operating closer to the efficiency ceiling.

FreeBSD’s network stack is described as delivering lower latency and higher throughput compared to default Linux settings. hamradio.my

Lower latency often correlates with fewer wakeups and less wasted CPU time: i.e., better power efficiency under load.

Notice the LiGNUxers frame the gain as a victory and ignore that Linux may have simply been playing catch-up and this exposed horrible inefficiency.

BSD might have been ahead, but nobody was measuring power.

FreeBSD is a complete OS with unified kernel + userland, not a mix‑and‑match ecosystem. CyberPanel

-This reduces fragmentation and can reduce overhead in areas like syscall paths, network stack transitions, memory allocation, and context switching. These architectural advantages translate into power efficiency without “power patches.”