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Date:      Thu, 14 May 2015 11:29:38 -0400
From:      mfv <mfv@bway.net>
To:        "William A. Mahaffey III" <wam@hiwaay.net>
Cc:        "FreeBSD Questions !!!!" <freebsd-questions@freebsd.org>
Subject:   Re: sysctl question
Message-ID:  <20150514112938.69eb9dac@gecko4>
In-Reply-To: <5554BABC.6080705@hiwaay.net>
References:  <55541052.6020802@hiwaay.net> <20150514055826.01e841ae@gecko4> <5554ABEF.4070300@hiwaay.net> <5554AD9D.9060201@hiwaay.net> <20150514105902.319e5f3f@gecko4> <5554BABC.6080705@hiwaay.net>

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On Thu, 14 May 2015 10:16:03 -0453
"William A. Mahaffey III" <wam@hiwaay.net> wrote:

> On 05/14/15 10:05, mfv wrote:
> > On Thu, 14 May 2015 09:20:04 -0453
> > "William A. Mahaffey III" <wam@hiwaay.net> wrote:
> >
> >> On 05/14/15 09:12, William A. Mahaffey III wrote:
> >>> On 05/14/15 05:04, mfv wrote:
> >>>> Hello William,
> >>>>
> >>>> I had the same problem using amdtemp but used the sysctl setting
> >>>> "dev.amdtemp.%d.sensor_offset" to make it more accurate. The
> >>>> value was determined by comparing the unadjusted value of
> >>>> admtemp with the value shown in the BIOS.  In my case the setting
> >>>> in /etc/sysctl.conf is:
> >>>>
> >>>>    dev.amdtemp.0.sensor_offset=24
> >>>>
> >>>> A room thermometer was also helpful to measure the difference by
> >>>> comparing the difference between the room temperature and the
> >>>> BIOS after the CPU was placed under load.
> >>>>
> >>>> To read the value I then bound the F2-key in csh.cshrc file as
> >>>> follows:
> >>>>
> >>>>     bindkey -c "^[OQ" 'sysctl -e dev.amdtemp.0.core0'
> >>>>
> >>>> The results of the reading are not as accurate as I would like
> >>>> but are an improvement.
> >>>>
> >>>>       Cheers ...                                 __o
> >>>>                                                _ \<,_
> >>>>       Marek                                   (+)/ (+)
> >>>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >>> P.S. Is there a way to set this on the fly, w/o a reboot ?
> >>> TIA :-) ....
> >>>
> >>
> >> [root@kabini1, /etc, 9:18:34am] 369 % sysctl
> >> dev.amdtemp.0.sensor_offset=24 sysctl: unknown oid
> >> 'dev.amdtemp.0.sensor_offset' [root@kabini1, /etc, 9:18:36am] 370 %
> >> sysctl amdtemp.0.sensor_offset=24 sysctl: unknown oid
> >> 'amdtemp.0.sensor_offset' [root@kabini1, /etc, 9:18:37am] 371 %
> >> sysctl -A | grep -i amdtemp dev.amdtemp.0.%desc: AMD CPU On-Die
> >> Thermal Sensors dev.amdtemp.0.%driver: amdtemp
> >> dev.amdtemp.0.%parent: hostb5
> >> dev.amdtemp.0.sensor0.core0: 10.0C
> >> [root@kabini1, /etc, 9:18:41am] 372 % uname -a
> >> FreeBSD kabini1.local 9.3-RELEASE-p13 FreeBSD 9.3-RELEASE-p13 #0:
> >> Tue Apr  7 03:01:12 UTC 2015
> >> root@amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC
> >> amd64 [wam@kabini1, ~, 9:19:39am] 399 %
> >>
> >>
> > Yes, it is possible to do it on the fly:
> >
> > [10:55] ~ >
> > dev.amdtemp.0.core0.sensor0=39.7C
> >
> > [10:55] ~ > sudo sysctl dev.amdtemp.0.sensor_offset=0
> > dev.amdtemp.0.sensor_offset: 24 -> 0
> >
> > [10:55] ~ >
> > dev.amdtemp.0.core0.sensor0=15.7C
> >
> > [10:55] ~ > sudo sysctl dev.amdtemp.0.sensor_offset=24
> > dev.amdtemp.0.sensor_offset: 0 -> 24
> >
> > [10:55] ~ >
> > dev.amdtemp.0.core0.sensor0=39.8C
> >
> > The 1st, 3rd and 5th command line are the results of the binding of
> > the F2-key to the sysctl output.
> >
> > The 2nd command line sets the offset to the default of 0 while the
> > 4th command line sets it back to 24 which is normally set in
> > /etc/sysctl.conf.
> >
> > Your value will probably be different.
> >
> > Cheers ...
> >
> > Marek
> > _______________________________________________
> > freebsd-questions@freebsd.org mailing list
> > http://lists.freebsd.org/mailman/listinfo/freebsd-questions
> > To unsubscribe, send any mail to
> > "freebsd-questions-unsubscribe@freebsd.org"
> >
> 
> 
> When I tried as you did above as root (see farther above), it said 
> 'sysctl: unknown oid'. What version of FreeBSD are you using ? I'm on 
> 9.3R-p13, I suspect you might be on 10.1, & maybe that sysctl
> variable isn't available under 9.3R ....
> 
> 

You nailed it.  I just checked the man pages of amdtemp on the FreeBSD
website and discovered that the offset value was only introduced in the
10.0-RELEASE. I'm on the 10.1-RELEASE.

Sorry for the goose chase.


    Cheers ...                                 __o
                                             _ \<,_
    Marek                                   (+)/ (+)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~




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