high CPU fan speed on Supermicro X11 boards with Slack150

pisti · 03-09-2022, 10:07 AM

i use in two Supermicro 7039A-i servers X11DAi-N motherboards with Xeon Bronze 3104 and Xeon Silver 4216 CPUs with Slack142 and now Slack150. the problem is that the CPU fans when idle run constantly at high speed while under heavy load their speed reciprocally diminishes, even to a barely audible noise level ! as if the temperature control logic is turned upside down...? and that's pretty immediate, by the way !

now, i tried to influence fan speeds with freeipmi, ipmitool and IPMICFG but they succeed only to regulate the chassis fan speeds while CPU speeds seem to run at high speed, or perhaps even max blast (though there i am not sure). in any case, the current noise level is for my office pretty annoying, sigh...

is CPU speed controlled by the 5.15.19 kernel ?

any input is much appreciated !

Chuck56 · 03-11-2022, 07:59 AM

Quote:

Originally Posted by pisti

is CPU speed controlled by the 5.15.19 kernel ?

CPU speed is controlled by BIOS & cpufreq settings. In Slackware 15.0 you can modify /etc/default/cpufreq from ondemand to powersave and force the CPU to run at low speed. That should help keep the core temps down and the fan spinning slower. I'm not familiar with the Supermicro BIOS so those settings I'll leave for others to comment on.

As an aside, any possibility the servers have been cryptojacked?

pisti · 03-11-2022, 03:14 PM

thank you, Chuck56, for your feedback. now, you know, the CPU load is actually currently just zero, completely idle - but already the slightest work load lowers the CPU fan noise kind of proportionally but reciprocally ! no signs of being cryptojacked, so far....

regarding CPU speed i wouldn't want to lower their performance though i am not sure what impact the SCALING_GOVERNOR option has on compute frequency.

there must be an option to adjust CPU fan speeds or related temperature settings ... ?

mrmazda · 03-22-2022, 10:50 PM

What does the fan do if you boot a Knoppix stick or other live media?

pisti · 03-24-2022, 01:45 PM

good point, mrmazda, i will check that once there is some idle time on those servers... thanks.

in any case, the only way i was able to play a bit with the fan speeds was using Supermicro's IPMICFG tool which is set to :

Code:

IPMICFG -fan
Current Fan Speed Mode is [ Optimal Mode ]

Supported Fan modes:
0:Standard
1:Full
2:Optimal
4:Heavy IO

all my other attempts using freeipmi or ipmitool failed...or i didn't have (yet) the nerves to study/understand the logic behind the fan control system.

in sum : fan speed is 'ok' (tolerable but still loud) when idle, but as soon as i initiate a task, the (CPU?) fans go quiet, very very quiet(!) indeed, even when overloaded 70-80 times, but then immediately recover and crank up again once the task is done. in fact, i have this way here an audible mechanism telling me when a job has finished...not entirely a solution i could be happy with...

Jan K. · 03-24-2022, 03:36 PM

you need to define fan rpms for the settings... https://forums.servethehome.com/inde...ed-control.20/

pisti · 03-25-2022, 01:06 PM

thank you, Jan K., yes, i have seen that page a week ago or so, and even made myself a note to follow it up, but then life being bizi and a bit crazy...

in any case, thank you for your post - i finally followed that author's instructions and things worked out nicely. here my solution :

Code:

/etc/rc.d/rc.local :

# full speed :
ipmitool raw 0x30 0x45 0x01 0x01
# 25% speed zone 0
ipmitool raw 0x30 0x70 0x66 0x01 0x00 0x16
# 25% speed zone A
ipmitool raw 0x30 0x70 0x66 0x01 0x01 0x16

i monitored temperature here and there manually under very high CPU load, and things seem to stay stable...

Code:

ipmitool sensor | grep -i TEMP | grep CPU

CPU1 Temp | 43.000     | degrees C  | ok    | 5.000     | 5.000     | 10.000    | 86.000    | 91.000    | 91.000
CPU2 Temp | 48.000     | degrees C  | ok    | 5.000     | 5.000     | 10.000    | 86.000    | 91.000    | 91.000

most importantly - my office' noise level turned more tolerable this way... Jan, thanks again !

thread [SOLVED]

pisti · 03-25-2022, 01:37 PM

i was a bit too fast with marking this [SOLVED]...

my two dual-XEON Supermicro boxes are now indeed less noisy, so far so good !

BUT, they are calmest, most silent, when i throw 64 jobs at the two XEONs and reach a 70-fold or higher load level. this pattern doesn't make much sense to me - that's what i meant to be illogical as the temperature control logic appears to be turned upside down...? absolute temperatures are still well below 50°C.

i assume one needs to play with the temperature settings as well - although i feel we are getting into an area that borders to a doctorate...

Jan K. · 03-25-2022, 06:11 PM

SuperMicro invites end users to send mail, here https://www.supermicro.com/en/support

I'm certain they'll provide you some guidelines.