A SMC daemon for Intel MacBooks to run the fan harder when the machine is hot.
I find that my i9 MacBook Pro overheats without this. 🔥😑🔥
I haven't tested this program anywhere besides my 2018 MacBookPro15,1.
The program likely works on most Intel MacBooks, and maybe even ARM and Mac desktop computers. But, it might not work or even cause problems due to SMC keys being different.
You have been warned. Don't use this if you're not willing to check that it's working properly for you.
c++ -std=c++20 -framework IOKit -framework ApplicationServices ./fancurve.cc -o ./fancurve
./install.sh
This installs fancurve in /Library/LaunchDaemons so it starts on boot.
./fancurve can also run without being installed.
(But, avoid both installing it and running it standalone, or else the two processes will fight over the fan.)
By default, on a tty, the program will emit a rolling log of the target fan speed expressed as a percentage, as well as the temperature and SMC key of the sensor primarily responsible for causing elevated fan speed.
The algorithm for setting the fan speed is approximately: each SMC temperature sensor is read, and the value is clamped and linearly normalized to a 0%–100% range. Then, the maximum percentage from this process is applied as the speed of all fans. This process is repeated every couple of seconds.
For most temperature sensors, the clamping range is 60°C to 70°C, but there are alternate hardcoded ranges. For example, the CPU core temp sensors have a much higher range (allowing the cores to get much hotter than 70°C before raising the fan speed), while the laptop exterior case temp sensors have a much lower range (maxing out the fan speed above any skin-unsafe temperature).