Ubuntu Manpage: thinkfan.conf - YAML-formatted config for thinkfan(1)

Provided by: thinkfan_1.3.1-4build1_amd64

NAME

       thinkfan.conf - YAML-formatted config for thinkfan(1)

DESCRIPTION

YAML is a very powerful, yet concise notation for structured data. Its full specification is available
at https://yaml.org/spec/1.2/spec.html. Thinkfan uses only a small subset of the full YAML syntax, so it
may be helpful, but not strictly necessary for users to take a look at the spec.

The most important thing to note is that indentation is syntactically relevant. In particular, tabs
should not be mixed with spaces. We recommend using two spaces for indentation, like it is shown below.

The thinkfan config has three main sections:

sensors: Where temperatures should be read from. All hwmon-style drivers are supported, as well as
/proc/acpi/ibm/thermal, and, depending on the compile-time options, libatasmart (to read
temperatures directly from hard disks) and NVML (via the proprietary nvidia driver).

fans: Which fans should be used (currently only one allowed). Support for multiple fans is
currently in development and planned for a future release. Both hwmon-style PWM controls and
/proc/acpi/ibm/fan can be used.

levels: Maps temperatures to fan speeds. A “simple mapping” just specifies one temperature as the
lower and upper bound (respectively) for a given fan speed. In a “detailed mapping”, the
upper and lower bounds are specified for each driver/sensor configured under sensors:. This
mode should be used when thinkfan is monitoring multiple devices that can tolerate different
amounts of heat.

Under each of these sections, there must be a list of key-value maps, each of which configures a sensor
driver, fan driver or fan speed mapping.

SENSOR & FAN DRIVERS

For thinkfan to work, it first needs to know which temperature sensor drivers and which fan drivers it
should use. The mapping between temperature readings and fan speeds is specified in a separate config
section (see the FAN SPEEDS section below).

Sensor Syntax
The entries under the sensors: section can specify hwmon, thinkpad_acpi, NVML or atasmart drivers, where
the latter two must be enabled at compile-time. There can be any number (greater than zero) and
combination of hwmon, tpacpi, nvml and atasmart entries. However there may be at most one instance of
the tpacpi entry.

sensors:
- hwmon: hwmon-path
name: hwmon-name
indices: index-list
correction: correction-list
optional: bool-allow-errors

- tpacpi: /proc/acpi/ibm/thermal
indices: index-list
correction: correction-list
optional: bool-allow-errors

- nvml: nvml-bus-id
correction: correction-list
optional: bool-allow-errors

- atasmart: disk-device-file
correction: correction-list
optional: bool-allow-errors

- ...

Fan Syntax
Currently, thinkfan supports only one fan, so there can be only one entry in the list. Support for
multiple fans is currently in development and planned for a future release. The fan is either an hwmon
fan:

fans:
- hwmon: hwmon-path
name: hwmon-name
indices: index-list

or a tpacpi fan:

fans:
- tpacpi: /proc/acpi/ibm/fan

Values
hwmon-path There are three ways of specifying hwmon fans or sensors:

1) A full path of a “temp*_input” or “pwm*” file, like “/sys/class/hwmon/hwmon0/pwm1” or
“/sys/class/hwmon/hwmon0/temp1_input”. In this case, the “indices: index-list” and “name:
hwmon-name” entries are unnecessary since the path uniquely identifies a specific fan or
sensor.

Note that this method may lead to problems when the load order of the drivers changes across
bootups, because in the “hwmonX” folder name, the X actually corresponds to the load order.
Use method 2) or 3) to avoid this problem.

2) A directory that contains a specific hwmon driver, for example
“/sys/devices/platform/nct6775.2592”. Note that this path does not contain the load-order
dependent “hwmonX” folder. As long as it contains only a single hwmon driver/interface it is
sufficient to specify the “indices: index-list” entry to tell thinkfan which specific sensors
to use from that interface. The “name: hwmon-name” entry is unnecessary.

3) A directory that contains multiple or all of the hwmon drivers, for example
“/sys/class/hwmon”. Here, both the “name: hwmon-name” and “indices: index-list” entries are
required to tell thinkfan which interface to select below that path, and which sensors or
which fan to use from that interface.

hwmon-name The name of a hwmon interface, typically found in a file called “name”. This has to be
specified if hwmon-path is a base path that contains multiple hwmons. This method of
specifying sensors is particularly useful if the full path to a particular hwmon keeps
changing between bootups, e.g. due to changing load order of the driver modules.

index-list A YAML list [ X1, X2, ... ] that specifies which sensors, resp. which fan to use from a given
interface. Both /proc/acpi/ibm/thermal and also many hwmon interfaces contain multiple
sensors, and not all of them may be relevant for fan control.

• For hwmon entries, this is required if hwmon-path does not refer directly to a single
“tempXi_input” file, but to a folder that contains one or more of them. In this case, index-
list specifies the Xi for the “tempXi_input” files that should be used. A hwmon interface
may also contain multiple PWM controls for fans, so in that case, index-list must contain
exactly one entry.

• For tpacpi sensors, this entry is optional. If it is omitted, all temperatures found in
/proc/acpi/ibm/thermal will be used.

nvml-bus-id NOTE: only available if thinkfan was compiled with USE_NVML enabled.

The PCI bus ID of an nVidia graphics card that is run with the proprietary nVidia driver. Can
be obtained with e.g. “lspci | grep -i vga”. Usually, nVidia cards will use the open source
nouveau driver, which should support hwmon sensors instead.

disk-device-file
NOTE: only available if thinkfan was compiled with USE_ATASMART enabled.

Full path to a device file for a hard disk that supports S.M.A.R.T. See also the -d option
in thinkfan(1) that prevents thinkfan from waking up sleeping (mechanical) disks to read
their temperature.

correction-list (always optional)
A YAML list that specifies temperature offsets for each sensor in use by the given driver.
Use this if you want to use the “simple” level syntax, but need to compensate for devices
with a lower heat tolerance. Note however that the detailed level syntax is usually the
better (i.e. more fine-grained) choice.

bool-allow-errors (always optional, false by default)
A truth value (yes/no/true/false) that specifies whether thinkfan should accept errors when
reading from this sensor. Normally, thinkfan will exit with an error message if reading the
temperature from any configured sensor fails. Marking a sensor as optional may be useful for
removable hardware or devices that may get switched off entirely to save power.

FAN SPEEDS

The levels: section specifies a list of fan speeds with associated lower and upper temperature bounds.
If temperature(s) drop below the lower bound, thinkfan switches to the previous level, and if the upper
bound is reached, thinkfan switches to the next level.

Simple Syntax
In the simplified form, only one temperature is specified as an upper/lower limit for a given fan speed.
In that case, the lower-bound and upper-bound are compared only to the highest temperature found among
all configured sensors. All other temperatures are ignored. This mode is suitable for small systems
(like laptops) where there is only one device (e.g. the CPU) whose temperature needs to be controlled, or
where the required fan behaviour is similar enough for all heat-generating devices.

levels:
- [ fan-speed, lower-bound, upper-bound ]
- ...

Detailed Syntax
This mode is suitable for more complex systems, with devices that have different temperature ratings.
For example, many modern CPUs and GPUs can deal with temperatures above 80°C on a daily basis, whereas a
hard disk will die quickly if it reaches such temperatures. In detailed mode, upper and lower
temperature limits are specified for each sensor individually:

levels:
- speed: fan-speed
lower_limit: [ l1, l2, ... ]
upper_limit: [ u1, u2, ... ]
- ...

Values
fan-speed The possible speed values are different depending on which fan driver is used.

For a hwmon fan, fan-speed is a numeric value ranging from 0 to 255, corresponding to the PWM
values accepted by the various kernel drivers.

For a tpacpi fan on Lenovo/IBM ThinkPads and some other Lenovo laptops (see SENSORS & FAN
DRIVERS above), numeric values and strings can be used. The numeric values range from 0 to
7. The string values take the form "level lvl-id", where lvl-id may be a value from 0 to 7,
auto, full-speed or disengaged. The numeric values 0 to 7 correspond to the regular fan
speeds used by the firmware, although many firmwares don't even use level 7. The value
"level auto" gives control back to the firmware, which may be useful if the fan behavior only
needs to be changed for certain specific temperature ranges (usually at the high and low end
of the range). The values "level full-speed" and "level disengaged" take the fan speed
control away from the firmware, causing the fan to slowly ramp up to an absolute maximum that
can be achieved within electrical limits. Note that this will run the fan out of
specification and cause increased wear, though it may be helpful to combat thermal
throttling.

l1, l2, ...

u1, u2, ... The lower and upper limits refer to the sensors in the same order in which they were found
when processing the sensors: section (see SENSOR & FAN DRIVERS above). For the first level
entry, the lower_limit may be omitted, and for the last one, the upper_limit may be omitted.
For all levels in between, the lower limits must overlap with the upper limits of the
previous level, to make sure the entire temperature range is covered and that there is some
hysteresis between speed levels.

BUGS

       Report bugs on the github issue tracker:
       https://github.com/vmatare/thinkfan/issues

thinkfan 1.3.1                                    December 2021                                 THINKFAN.CONF(5)

NAME

DESCRIPTION

SENSOR & FAN DRIVERS

FAN SPEEDS

SEE ALSO

BUGS