Re: sysmon_envsys ENVSYS_INDICATOR state change reports

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

On Sun, 26 Aug 2012, Manuel Bouyer wrote:

> On Sun, Aug 26, 2012 at 11:47:46AM -0700, Paul Goyette wrote:
> > On Sun, 26 Aug 2012, Manuel Bouyer wrote:
> >
> > > Hello,
> > > while hacking on mfi(4), I found that, while sysmon_envsys(9) reports
> > > state change for ENVSYS_DRIVE sensors, such as:
> > > mfi0: normal state on 'mfi0:0' (online)
> > > mfi0: normal state on 'mfi0:1' (online)
> > >
> > > but it doesn't do for ENVSYS_INDICATOR sensors. All sensors starts
> > > in state ENVSYS_SINVALID, and the status gets updated later by
> > > calls to mfi_sensor_refresh() from sysmon_envsys.
> >
> > For these sensors, status should always be SVALID or SINVALID.  The
> > status is separate from the value, which for an indicator is either
> > 0 or 1.
>
> So we can't mention if a value is critical or not ?

Not currently.

> > > Why are changes to ENVSYS_INDICATOR nor reported, and would it make
> > > sense to have changes to ENVSYS_INDICATOR be reported too ?
> >
> > It would not be too difficult to change this behavior.
> >
> > Howver, what are the acceptable "values" for such an indicator?
> > This is really a boolean, so TRUE or FALSE might be valid.  But it
> > seems that all current uses are for detecting the presence or
> > absence of some sort of power source, so maybe PRESENT and ABSENT
> > should be used?  (The powerd(8) man page seems to indicate that
> > valid states would be CRITICAL or NORMAL, but I don't think that
> > makes sense.)
>
> Well, in the case of the BBU it would be better to display good or bad.
> ABSENT would be misleading, becase what we really want to report
> is that the BBU is present but bad.

I'm sure we could come up with dozens of pairs of values, GOOD/BAD,
TRUE/FALSE, PRESENT/ABSENT, CRITICAL/NORMAL, ...

> > An easy alternative would simply to mark the sensor as an INTEGER,
> > and only assign it values of 0 or 1.  Changes in INTEGER values can
> > be reported.
>
> But then what would envstat report ?

It would just show the integer value 0 or 1.  You can see an example 
using swsensor(4):

        modload -s type=Integer swsensor
        envstat -d swsensor
        modunload swsensor

> > The original design seems to have assumed that INDICATOR sensors
> > were only for system-wide power sources (AC adapters).
>
> I think we need a general-purpose boolean sensor.

It seems that envstat(8) already thinks that INDICATOR is a boolean.  It 
reports values of TRUE and FALSE.


It would be fairly easy to report changes in INDICATOR sensors, it's 
just a matter of what words to use in the reports!


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