NAME

       i8kmon - temperature monitor

SYNOPSIS

       i8kmon [<options>]

DESCRIPTION

       The i8kmon is a daemon that monitors the cpu temperature, and control the fan speed on some Dell laptops.
       It does that by means of regularly reading the system temperature, and choosing appropriate speed of  the
       fans.

       The change in the speed depends on a table of threshold. Inside i8kmon the default table of thresholds is
       as below

           set config(0) {{0 0}  -1  60  -1  65}
           set config(1) {{1 0}  50  70  55  75}
           set config(2) {{1 1}  60  80  65  85}
           set config(3) {{2 2}  70 128  75 128}

       This table can be customized at '/etc/i8kmon.conf', which will be read everytime i8kmon service starts.

       On Debian and derivated OSes, i8kmon starts in the background by default as a service.

OPTIONS

       i8kmon accepts the following command-line options when initiated by the user, not as a service:

       -nc, --nouserconfig
              Doesn't read ~/.i8kmon configfile, only /etc/i8kmon.conf.

       -v, --verbose
              Report hardware status and program actions on stdout.

       -t, --timeout <seconds>
              Specifies the interval at which the daemon checks the hardware status. Useful values  are  in  the
              range of 1-5 seconds. Default is 2 seconds.

CONFIGURATION

       As  said  before,  i8kmon  has  builtin default values of temperature thresholds. If users need, they can
       specify their own settings in configuration files /etc/i8kmon.conf and ~/.i8kmon. It is also possible  to
       specify values to others variables that change i8kmon behavior.

       The variables and values are as follows.

       set config(i8kfan)  /usr/bin/i8kfan
              i8kfan executable path

       set config(acpi)    "acpi"
              Filename  of  the  apci  executable.  i8kmon  uses acpi to query whether notebook is on-line or on
              battery.

       set config(use_conf)    1
              Set whether user configuration file must be read or not when user starting i8kmon. Default is 1.

       set config(verbose) 0
              Print verbose logs

       set config(timeout) 2
              Timeout. Default is 2.

       set config(t_high)  80
              Maximum high temperature. Default is 80.

       The following variables set fans speeds. If these variables are set at config file, i8kmon will not probe
       for them. The probe moment turns on fans at max speed.

       set status(leftspeed)   "0 1000 2000 3000"
              Speed values (rpm) of left fan at velocities 0, 1, 2, 3

       set status(rightspeed)   "0 1000 2000 3000"
              Speed values (rpm) of right fan at velocities 0, 1, 2, 3

       The  daemon defines 4 states (0, 1, 2, 3) with different combinations of fan speeds ({0 0}, {1 0}, {1 1},
       {2 2}) and for each state is defined the temperature thresholds which cause  the  fans  to  switch  to  a
       higher  or lower state. Each state can have different thresholds for operation on ac power or on battery.
       For example the following configuration:

              set config(0) {{0 0}  -1  60  -1  65}
              set config(1) {{1 0}  50  70  55  75}
              set config(2) {{1 1}  60  80  65  85}
              set config(3) {{2 2}  70 128  75 128}

       defines state 0 with both fans off, high threshold of 60 degrees (65 on battery)  and  low  threshold  -1
       degrees,  which  is  actually  never reached since 0 is the lowest temperature. When the high temperature
       threshold is reached the program switches to state 1 (left low, right off) which has a high threshold  of
       70  degrees  and a low threshold of 50 degrees. If on ac power the temperature drops below 50 the program
       will switch back to state 0, if it rises above 70 it will enter state 2, and so on.  For better operation
       the  temperature  ranges  should  be  overlapping  with  an hysteresis of at least 10 degrees, i.e. 1={50
       70},2={60 80} is better than 1={50 70},2={70 80}. It must be remembered that the low threshold of state 0
       must be -1 degrees and the high threshold of state 3 must be 128 degrees.

       If  the  laptop  has  only one fan, it is better to specify a '-' instead of the fan speed of the missing
       fan. For example:

              set config(2) {{1 -}  60  80  65  85}

FILES

       /proc/i8k
       /etc/i8kmon.conf
       /$HOME/.i8kmon

AUTHORS

       Vitor Augusto <vitorafsr@gmail.com>
       Massimo Dal Zotto <dz@debian.org>

COPYRIGHT

       i8kmon and all the i8kutils programs, scripts and other files  are  distributed  under  the  GNU  General
       Public  License  (GPL).  On Debian GNU/Linux systems, the complete text of the GNU General Public License
       can be found in `/usr/share/common-licenses/GPL'.

SEE ALSO

       i8kctl(1)