How to prevent underclocking when running with 1 redundant power supply

Craig Leres leres at freebsd.org
Sun Oct 27 21:07:15 UTC 2019


I have a nameserver running 11.3-RELEASE-p4. It has a Supermicro X9SRi-F 
motherboard in a 1U chassis with redundant PWS-406P-1R power supplies 
(400W each).

Site power is out thanks to a PG&E "public safety power shutdown" and I 
find that the system is really unhappy. It looks like it is 
underclocking due to one power supply not being powered:

     # sysctl dev.cpu.0.freq_levels dev.cpu.0.freq
     dev.cpu.0.freq_levels: 3001/80000 3000/80000 2900/75926 2700/69558 
2600/65698 2500/62669 2400/59709 2200/53206 2100/50412 2000/46962 
1800/41676 1700/38423 1600/35918 1500/33467 1300/28074 1200/25787
     dev.cpu.0.freq: 1200

I found powerd and tried this:

     powerd_enable="YES"
     powerd_flags="-a max -b max -n max"

which works... once it's started. Now I'm finding one system has a 
difficult time booting because powerd is started so late in the boot 
process.

Is there a sysctl I can put in loader.conf to disable this underclocking 
behavior?

Thanks!

		Craig


More information about the freebsd-hackers mailing list