Re: Noisy ipmi0 after bootup? (really other kernel noise)

[Paul Goyette <paul%whooppee.com@localhost>]

On Mon, 8 Sep 2008, Simon Burge wrote:

> > OK, if you apply the attached patches, you should see the following
> > changes:
> >
> > 1. ipmi should report CRITUNDER events for the fans that are at 0 RPM
> >
> > 2. you should get only one event for each fan
>
> With this I get:
>
>    ipmi0: critical under limit on 'Fan8/CPU2'
>    ipmi0: critical under limit on 'Fan7/CPU1'
>    ipmi0: critical under limit on 'Fan6'
>    ipmi0: critical under limit on 'Fan5'
>    ipmi0: critical under limit on 'Fan4'
>
> All "under", and no double messages.  There's still is question of why
> these are reported at all - since the value is always zero I suspect
> they really don't have fans, but not sure how we should detect this.

OK, the results are as I expected.  I already committed the changes to 
sysmon to prevent the double notifications, and with your confirmation 
here I'll go ahead and commit the ipmi changes to differentiate between 
over-limit and under-limit conditions.

As for detecting missing fans, ideally it would be the physical sensor's 
and/or BIOS's job to figure out that there's nothing attached to the fan 
header.  I'm not a hardware type, but I would expect that it could 
detect that there was zero current flowing and properly report a "not
present" condition.

Others have suggested that we could ignore fan sensors that have never 
reported a non-zero value, but I'm not sure that's the right answer.  As 
you can see from ipmitool output, it's reporting a "nr" (not rotating) 
state, not "na".

> And the output of "ipmitool ... sensor":
>
> CPU Temp 1       | 30.000     | degrees C  | ok    | na        | na        | na 
>        | 76.000    | 78.000    | 80.000
> CPU Temp 2       | 24.000     | degrees C  | ok    | na        | na        | na 
>        | 76.000    | 78.000    | 80.000
> CPU Temp 3       | na         | degrees C  | na    | na        | na        | na 
>        | 76.000    | 78.000    | 80.000
> CPU Temp 4       | na         | degrees C  | na    | na        | na        | na 
>        | 76.000    | 78.000    | 80.000
> Sys Temp         | 28.000     | degrees C  | ok    | na        | na        | na 
>        | 76.000    | 78.000    | 80.000
> CPU1 Vcore       | 1.192      | Volts      | ok    | 1.056     | 1.064     | 
> 1.072     | 1.624     | 1.632     | 1.640
> CPU2 Vcore       | 1.192      | Volts      | ok    | 1.056     | 1.064     | 
> 1.072     | 1.624     | 1.632     | 1.640
> 3.3V             | 3.312      | Volts      | ok    | 2.912     | 2.928     | 
> 2.944     | 3.648     | 3.664     | 3.680
> 5V               | 4.992      | Volts      | ok    | 4.416     | 4.440     | 
> 4.464     | 5.520     | 5.544     | 5.568
> 12V              | 11.808     | Volts      | ok    | 10.464    | 10.560    | 
> 10.656    | 13.344    | 13.440    | 13.536
> -12V             | -12.300    | Volts      | ok    | -10.500   | -10.600   | 
> -10.700   | -13.300   | -13.400   | -13.500
> 1.5V             | 1.488      | Volts      | ok    | 1.296     | 1.312     | 
> 1.328     | 1.664     | 1.680     | 1.696
> 5VSB             | 4.896      | Volts      | ok    | 4.416     | 4.440     | 
> 4.464     | 5.520     | 5.544     | 5.568
> VBAT             | 3.216      | Volts      | ok    | 2.912     | 2.928     | 
> 2.944     | 3.648     | 3.664     | 3.680
> Fan1             | 6300.000   | RPM        | ok    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan2             | 6500.000   | RPM        | ok    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan3             | 6100.000   | RPM        | ok    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan4             | 0.000      | RPM        | nr    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan5             | 0.000      | RPM        | nr    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan6             | 0.000      | RPM        | nr    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan7/CPU1        | 0.000      | RPM        | nr    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Fan8/CPU2        | 0.000      | RPM        | nr    | 200.000   | 300.000   | 
> 400.000   | na        | na        | na
> Intrusion        | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> Power Supply     | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> CPU0 Internal E  | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> CPU1 Internal E  | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> CPU Overheat     | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> Thermal Trip0    | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
> Thermal Trip1    | 0x0        | discrete   | 0x0000| na        | na        | na 
>        | na        | na        | na
>
>
> One more thing to notice - are the ipmi sensors in some reverse-ordered
> linked list?  The order of the sensors from envstat seems reversed.

Looks like internally to ipmi.c, the sensors are added to its own SLIST,
and then later on we walk through this list from head to tail to attach 
the sensors to sysmon.  This would have the explicit effect of reversing 
the list's order.  If this is particularly annoying, it should not be 
too difficult to change this from using an SLIST to SIMPLEQ.

Does maintaining the order of the sensor list appeal to others?


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