Hi,
I started to use lm_sensors to monitor my hardware. In particular, I want to
monitor temperature and fan functionality.
The system has an Intel D865GBF ATX Mainboard, with a Pentium 4 3 GHz processor,
800 MHz FSB, 1 MB Cache. I'm using lm_sensors version 2.9.1 that came with SUSE
10.0.
sensors-detect went fine, it detected the LM85 sensor chip "lm85b-i2c-0-2e";
start of the lm_sensors service as well, then calling sensors got:
CPU_Fan: 2669 RPM (min = 4000 RPM) ALARM
fan2: 0 RPM (min = 0 RPM)
fan3: 0 RPM (min = 0 RPM)
fan4: 0 RPM (min = 0 RPM)
CPU: +45 C (low = +10 C, high = +50 C)
Board: +36 C (low = +10 C, high = +35 C) ALARM
Remote: +37 C (low = +10 C, high = +35 C) ALARM
Oops, obviouslsy too much alarms for my taste. ;-)
So I learned that I have to configure /etc/sensors.cfg.
First, I wanted to check the measured values. So I rebooted and looked into the
BIOS read-out.
My BIOS reports the CPU temperature to be 56?C, System Zone 1 as 40?C, and
System Zone 2 as 45?C. (Wherever zone 1 and 2 are -- I assume that they match
temp2_* and temp3_* whereas temp1_* is the CPU.)
The CPU fan speed is the same, so that doesn't need any adaption.
So here's my first question:
Is it best practice to assume that the BIOS values are OK and to add compute
statements to increase the lm_sensors values to match them?
Is the relation between BIOS measurement and sensors measurement usually linear?
I.e., do I just add and subtract the difference in a compute statement?
Or does your experience tell that this needs some scale factor as well?
And my second question:
The semantics of the temperature limits in sensors.conf are still unclear to me.
There is temp#_min, temp#_max, temp#_hyst, and temp#_over.
min and max are not explained.
hyst and over are not used in the LM85 example configuration.
As far as I understood, if a temperature gets > temp#_over, ALARM is turned on;
and if it gets (subsequently) < temp#_hyst, ALARM is turned off again.
But what happens if the temperature is below temp#_min or above temp#_max?
How is the relation between these two vars and hyst/over?
In addition, the documentation of lm85 mentions other sensors.conf variables
named zone#_{limit,hyst,range,critical} which aren't used at all. It looks as if
the documentation is out of date and these variables don't exist any more. Is
that assumption true?
Last, the documentation mentions a /proc interface. I gather that this got
replaced by the /sys interface. There I find files/variables named
temp#_auto_temp_* that look interesting. Is there any documentation for them?
Sorry for these many questions. If there is documentation that I haven't found
and that would answer them, I'd also appreciate any hint to it.
Best,
Joachim
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Joachim Schrod Email: jschrod at acm.org
Roedermark, Germany
