3 breezed - Fan control daemon
6 \fBbreezed\fP [\fBoptions\fP]
9 \fBbreezed\fP is a daemon to adjust the fan speed according to the
10 computer temperature. It should be started through the adequate script
13 Every 5s, \fBbreezed\fP gathers all integer values from the thermal
14 files, and takes the max as the overall temperature T. It then
15 computes the highest fan speed whose temperature threshold is lower
16 than T. If that speed is above the current speed, the daemon changes
17 the fan speed accordingly. Otherwise it computes the lowest fan speed
18 whose temperature threshold is two degrees above T, and sets the fan
19 speed one level below. This two degree gap avoids too many
20 oscillations. Also, the daemon waits for at least 30s after any change
21 of the fan speed before reducing it. The fan speed is set by writing
22 "level <level>" into the specified fan file.
24 Options can not be specified twice, neither on the command line nor in
25 the configuration file.
28 .IP "\fB-h | --help\fP" 10
29 display help and exits
30 .IP "\fB-v | --version\fP" 10
31 display the version number and exits
32 .IP "\fB-d | --debug\fP" 10
34 .IP "\fB-cf | --configuration-file <file>\fP" 10
35 set the configuration file (default is /etc/breezed.conf)
36 .IP "\fB-ncf | --no-configuration-file\fP" 10
37 prevent the reading of a configuration file
38 .IP "\fB-tf | --thermal-file <file1>[,file2]...\fP" 10
39 set the files to spool for temperatures.
40 .IP "\fB-ff | --fan-file <file>\fP" 10
41 set the file to control the fan speed.
42 .IP "\fB-tt | --temperature-thresholds <temp1>[,temp2]...\fP" 10
43 set the temperature thresholds.
45 .SH "CONFIGURATION FILE"
47 The configuration file is a succession of lines, each starting with
48 one of the three keywords thermal_files, fan_file or
49 temperature_thresholds, followed by the same parameter values as for
50 the command line arguments. The default configuration file is located
55 If a configuration file exists, the standard way to start breezed is
56 to run it without arguments.
58 Starting it with all the arguments on the commande line can be done
61 breezed --no-configuration-file \
62 --thermal-files /proc/acpi/thermal_zone/THM0/temperature,/proc/acpi/thermal_zone/THM1/temperature \
63 --fan-file /proc/acpi/ibm/fan \
64 --temperature-thresholds 52,54,56,58,60,62,64
66 which specifies that when the temperature raises above 52C, the fan
67 level should be 1, when the temperature raises above 54C it should be
68 2, etc. The maximum speed level 7 should be chosen for temperatures
71 Due to the two degrees gap between the thresholds to increase and the
72 thresholds to decrease the temperature, it will for instance remains
73 at speed 1 until the temperature goes down to 50C.
75 Because it takes into account all the values found in the thermal
76 files, you can use as well /proc/acpi/thermal_zone/THM?/temperature or
77 /proc/acpi/ibm/thermal.
81 Written by Francois Fleuret <francois@fleuret.org>. Permission is
82 granted to copy, distribute and/or modify this document under the