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)