2 Breezed is a small daemon to control the speed of the fan,
3 depending on the current temperature of the computer. I have tested
4 it only on a Thinkpad X61s.
8 You can install it simply by running as root
12 and de-install it with
16 You must have a configuration file in /etc/breezed.conf. Only one
17 is currently provided in the archive, and it corresponds to the
18 settings _I_ picked for _my_ Lenovo X61s.
20 I have no idea if these settings are safe on this laptop (I guess
21 so, since I have been using them for a few months now and it works
22 perfectly), and I suspect they are not safe for another laptop.
26 Breezed scans the temperatures every 5s and sets the fan speed
27 according to a series of thresholds.
29 Unfortunately, if the fan speed is set directly according to these
30 temperature thresholds, it creates oscillations: The fan goes up,
31 temperature goes down, hence fan goes down, temperature goes up,
34 To mitigate such phenomenons, the daemon waits at least 30s after
35 the last change before reducing the fan speed, and the actual
36 thresholds to decrease the fan speed are two degrees below the
37 provided thresholds, which are used when increasing the fan
38 speed. This creates a stability area of two degrees, which seems to
39 be enough. Please let me know if you have problem with the
40 resulting overall behavior.
44 The breezed executable can read a configuration file (which is
45 /etc/breezed.conf by default, but that you can specify with
46 --configuration-file <file>) or get the various parameters on the
49 The thermal files can be specified either with the --thermal-files
50 options on the command line or the thermal_files keyword in the
51 configuration file. The provided value should be a comma-separated
52 list of filenames. When it want to pool the temperature, the daemon
53 will read those files and compute the maximum integer value they
56 The fan file can be specified with either --fan-file or the
57 fan_file keyword. The specified file will be used by the daemon to
58 control the fan speed by writing "level n" into it.
60 The temperature thresholds can be specified either with the
61 --temperature-thresholds argument, or with the
62 temperature_thresholds keyword in the configuration file. The
63 provided value should be a comma separated list of integers. The
64 first one is actually ignored and forced to -1. Each value states
65 which temperature should trigger the given level.
67 For instance, my X61s has 8 fan levels, from 0 to 7. The thresholds
68 I picked are -1,52,54,56,58,60,62,64. Hence, when the temperature
69 reaches 52C, the fan is set to level 1, when it reached 54C it is
70 set to level 2, etc. The maximum speed level 7 is chosen for any
71 temperature equal or greater than 64C. As said above, the
72 temperature to decrease the speed has to be two degrees below the
73 provided thresholds. Hence, the temperature of my X61s has to go
74 down to 50C (52C - 2) for the fan to switch off. Also, the daemon
75 waits at least 30s before reducing the speed of the fan.
79 I wrote this daemon for my personal usage on a X61s, and using it
80 may damage your hardware.
82 On Thinkpads you have to allow the module thinkpad_acpi to set the
83 fan speed, which is not allowed by default in Debian. To do so, you
84 have to have a file /etc/modprobe.d/thinkpad_acpi.modprobe
87 ---------------------------- snip snip -------------------------------
88 options thinkpad_acpi fan_control=1
89 ---------------------------- snip snip -------------------------------
92 Francois Fleuret (francois@fleuret.org)