After boot was: dev.hwpstate.0.freq_settings: 3500/-1 3500/-1 1550/-1 dev.cpu.0.freq_levels: 3500/-1 3500/-1 1550/-1 dev.cpu.0.freq: 1550 After set: dev.cpu.0.freq=3500 perfomance degraded to ~50% Returning dev.cpu.0.freq=1550 does not help with performance. 11.1-STABLE FreeBSD 11.1-STABLE r328439M amd64 Ryzen 1300X, no overclock, fixed freq and Voltage in BIOS.
If this is also true on CURRENT, it looks like a buggy BIOS. Your BIOS isn't reporting P-states via ACPI or you would see a second positive number instead of "/-1". It's possible the BIOS bug also breaks P-state setting. If a BIOS update is available from your vendor, consider applying it. If this works on CURRENT, great. I don't support stable branches, so I would just unsubscribe from this bug in that case. In either case, I'd suggest rebooting and just not setting dev.cpu.0.freq (leaving the machine in P0). At idle, FreeBSD enters power-saving C-states and won't consume any more power than if you were also downclocked.
(In reply to Conrad Meyer from comment #1) Update BIOS, remove fixed freq in BIOS. dev.hwpstate.0.freq_settings: 3500/4331 3000/3450 1550/1331 dev.cpu.0.freq_levels: 3500/4331 3000/3450 1550/1331 on latest 11.1 sorry for noise. PS: probably proper thing to not set freq if xxxx/-1 in dev.hwpstate.0.freq_settings to prevent performance degradation.
(In reply to rozhuk.im from comment #2) > PS: probably proper thing to not set freq if xxxx/-1 in > dev.hwpstate.0.freq_settings to prevent performance degradation. This should still work. I think the problem was buggy BIOS.