Dual CPU Support

[BadCo-NZ]

Hello again,

Is it possible to enable dual CPU support and change fan speed based on the hottest one?

Current path:

/sys/devices/platform/coretemp.0/hwmon/hwmon*/temp1_input

Additional path:

/sys/devices/platform/coretemp.1/hwmon/hwmon*/temp1_input

Thanks!

[petersulyok]

Hi,

This value here represents the temperature of the CPU package, not a single core. I assume it represents all of them.
Here is an real-life example from my machine:

coretemp-isa-0000
Adapter: ISA adapter
Package id 0:  +32.0°C  (high = +74.0°C, crit = +82.0°C)
Core 0:        +29.0°C  (high = +74.0°C, crit = +82.0°C)
Core 1:        +31.0°C  (high = +74.0°C, crit = +82.0°C)
Core 2:        +31.0°C  (high = +74.0°C, crit = +82.0°C)
Core 3:        +31.0°C  (high = +74.0°C, crit = +82.0°C)

Cheers,

Peter

[BadCo-NZ]

Hi Peter,

Yeah I noticed it was the package temperature, however I have two packages and want to base the fan speed on the hottest one, usually the rear CPU is hotter then the front CPU due to front-to-back airflow.

coretemp-isa-0000
Adapter: ISA adapter
Package id 0:  +57.0°C  (high = +75.0°C, crit = +85.0°C)
Core 0:        +50.0°C  (high = +75.0°C, crit = +85.0°C)
Core 1:        +48.0°C  (high = +75.0°C, crit = +85.0°C)
Core 2:        +47.0°C  (high = +75.0°C, crit = +85.0°C)
Core 3:        +50.0°C  (high = +75.0°C, crit = +85.0°C)
Core 4:        +49.0°C  (high = +75.0°C, crit = +85.0°C)
Core 5:        +51.0°C  (high = +75.0°C, crit = +85.0°C)

coretemp-isa-0001
Adapter: ISA adapter
Package id 1:  +48.0°C  (high = +75.0°C, crit = +85.0°C)
Core 0:        +45.0°C  (high = +75.0°C, crit = +85.0°C)
Core 1:        +39.0°C  (high = +75.0°C, crit = +85.0°C)
Core 2:        +41.0°C  (high = +75.0°C, crit = +85.0°C)
Core 3:        +42.0°C  (high = +75.0°C, crit = +85.0°C)
Core 4:        +42.0°C  (high = +75.0°C, crit = +85.0°C)
Core 5:        +42.0°C  (high = +75.0°C, crit = +85.0°C)

[petersulyok]

I see. We need to support multiple CPUs here.

[petersulyok]

Please take a look into this commit. It implements multiple CPU support.

[petersulyok]

This feature request has been implemented in release v1.1.0.

[BadCo-NZ]

Nice work @petersulyok, unfortunately I haven't had a chance to test it yet, but will report back when I do.

[petersulyok]

Hi @BadCo-NZ, I'm working on a pyudev based hardware recognition code and I would need your help, since you have multiple Intel CPUs on your motherboard. Would you be so kind as to run the following command on your computer?

udevadm info --export-db

and check these kind of sections for all CPUs in the output:

P: /devices/platform/coretemp.0
M: coretemp.0
R: 0
U: platform
E: DEVPATH=/devices/platform/coretemp.0
E: MODALIAS=platform:coretemp
E: USEC_INITIALIZED=2837283
E: ID_PATH=platform-coretemp.0
E: ID_PATH_TAG=platform-coretemp_0

I would like to know if the values of MODALIAS= variable would be the same for all CPUs.
Please let me know if I wasn't clear on this request.

[BadCo-NZ]

Here you go! Looks like MODALIAS is 1 instead of 0 for the second CPU.

P: /devices/platform/coretemp.0
M: coretemp.0
R: 0
U: platform
E: DEVPATH=/devices/platform/coretemp.0
E: SUBSYSTEM=platform
E: MODALIAS=platform:coretemp
E: USEC_INITIALIZED=8370938
E: ID_PATH=platform-coretemp.0
E: ID_PATH_TAG=platform-coretemp_0

P: /devices/platform/coretemp.0/hwmon/hwmon6
M: hwmon6
R: 6
U: hwmon
E: DEVPATH=/devices/platform/coretemp.0/hwmon/hwmon6
E: SUBSYSTEM=hwmon

P: /devices/platform/coretemp.1
M: coretemp.1
R: 1
U: platform
E: DEVPATH=/devices/platform/coretemp.1
E: SUBSYSTEM=platform
E: MODALIAS=platform:coretemp
E: USEC_INITIALIZED=8370956
E: ID_PATH=platform-coretemp.1
E: ID_PATH_TAG=platform-coretemp_1

P: /devices/platform/coretemp.1/hwmon/hwmon7
M: hwmon7
R: 7
U: hwmon
E: DEVPATH=/devices/platform/coretemp.1/hwmon/hwmon7
E: SUBSYSTEM=hwmon

[petersulyok]

Thanks, this helped a lot.
Based on the MODALIAS=platform:coretemp attribute all CPUs (belonging to the coretemp module) can be queried and in a second step the proper HWMON path can be also read. Looks promising.