Man Linux: Main Page and Category List


       gkrellm - The GNU Krell Monitors


       gkrellm  [ --help ] [ -t | --theme dir ] [ -g | --geometry +x+y ] [ -wm
       ] [ -w | --withdrawn ] [ -c |  --config  suffix  ]  [  -nc  ]  [  -f  |
       --force-host-config  ]  [  -demo  ]  [ -p | --plugin ] [ -s |
       --server hostname ] [ -P | --port server_port ] [ -l | --logfile path ]


       With  a  single  process, gkrellm manages multiple stacked monitors and
       supports applying themes to  match  the  monitors  appearance  to  your
       window manager, Gtk, or any other theme.

       ·   SMP CPU, Disk, Proc, and active net interface monitors with LEDs.

       ·   Internet  monitor  that displays current and charts historical port

       ·   Memory and swap space usage meters and a system uptime monitor.

       ·   File system meters show capacity/free space and can mount/umount.

       ·   A mbox/maildir/MH/POP3/IMAP mail monitor which can  launch  a  mail
           reader or remote mail fetch program.

       ·   Clock/calendar and hostname display.

       ·   Laptop Battery monitor.

       ·   CPU/motherboard  temperature/fan/voltages display with warnings and
           alarms.  Linux  requires  a  sensor  configured  sysfs,  lm_sensors
           modules or a running mbmon daemon.  FreeBSD can also read the mbmon
           daemon.  Windows requires MBM.

       ·   Disk temperatures if there’s a running hddtemp daemon.

       ·   Multiple monitors managed by a  single  process  to  reduce  system

       ·   A timer button that can execute PPP or ISDN logon/logoff scripts.

       ·   Charts are autoscaling with configurable grid line resolution, or

       ·   can be set to a fixed scale mode.

       ·   Separate  colors for "in" and "out" data.  The in color is used for
           CPU user time, disk read, forks, and net  receive  data.   The  out
           color  is used for CPU sys time, disk write, load, and net transmit

       ·   Commands can be configured to run when monitor labels are  clicked.

       ·   Data  can  be  collected from a gkrellmd server running on a remote

       ·   gkrellm is plugin capable  so  special  interest  monitors  can  be

       ·   Many themes are available.

       · Top frame

              Btn 1  Press and drag to move gkrellm window.

              Btn 3  Popup main menu.

       · Side frames

              Btn 2  Slide gkrellm window shut (Btn1 if -m2 option).

              Btn 3  Popup main menu.

       · All charts

              Btn 1  Toggle draw of extra info on the chart.

              Btn 3  Brings up a chart configuration window.

       · Inet charts

              Btn 2  Toggle between port hits per minute and hour.

       · Most panels

              Btn 3  Opens  the  configuration  window directly to a monitor’s
                     configuration page.

       · File System meter panels

              Btn 1,2
                     Toggle  display  of  label  and  fs  capacity   scrolling
                     display.   The  mount  button runs mount/umount commands.
                     If ejectable, left click the eject button to  open  tray,
                     right click to close.

       · Mem and Swap meter panels

              Btn 1,2
                     Toggle  display  of  label  and  memory  or swap capacity
                     scrolling display.

       · Mailbox monitor message count button

              Btn 1  Launch a mail reader program.  If  options  permit,  also
                     stop animations and reset remote message counts.

              Btn 2  Toggle  mail  check  mute  mode  which inhibits the sound
                     notify  program,  and  optionally   inhibits   all   mail

       · Mailbox monitor envelope decal

              Btn 1  Force a mail check regardless of mute or timeout state.

       · Battery monitor panel

              Btn 1  On the charging state decal toggles battery minutes left,
                     percent level, and charge rate display.

              Btn 2  Anywhere on the panel also toggles the display.

       · Keyboard shortcuts

              F1     popup the user config window.

              F2     popup the main menu.

                     previous theme or theme alternative.

                     next theme or theme alternative.

                     previous theme, skipping any theme alternatives.

                     next theme, skipping any theme alternatives.

       If a command has been configured to be launched for a monitor,  then  a
       button  will  appear  when  the mouse enters the panel of that monitor.
       Clicking the button will launch the command.

       A right button mouse click on the side or top  frames  of  the  gkrellm
       window  will pop up a user configuration window where you can configure
       all  the  builtin  and  plugin  monitors.   Chart  appearance  may   be
       configured  by  right  clicking  on a chart, and right clicking on many
       panels will open the configuration window directly to the corresponding
       monitor’s configuration page.


       --help Displays this manual page.

       -t, --theme dir
              gkrellm  will  load  all  theme  image files it finds in dir and
              parse the gkrellmrc file if one exists.  This  option  overrides
              the loading of the last theme you configured to be loaded in the
              Themes configuration window.  Theme changes are not  saved  when
              gkrellm is run with this option.

       -g, --geometry +x+y
              Makes  gkrellm  move  to  an  (x,y)  position  on  the screen at
              startup.  Standard X window geometry position (not size) formats
              are  parsed,  ie +x+y -x+y +x-y -x-y.  Except, negative geometry
              positions are not recognized (ie +-x--y ).

       -wm    Forces gkrellm to start up with window manager decorations.  The
              default is no decorations because there are themed borders.

       -w, --withdrawn
              gkrellm  starts  up  in  withdrawn  mode  so  it can go into the
              Blackbox slit (and maybe WindowMaker dock).

       -c, --config suffix
              Use alternate config files  generated  by  appending  suffix  to
              config  file  names.   This  overrides  any previous host config
              which may have been setup with the below option.

       -f, --force-host-config
              If  gkrellm  is  run  once  with  this  option  and   then   the
              configuration  or  theme  is  changed, the config files that are
              written will have a -hostname appended to them.  Subsequent runs
              will  detect  the  user-config-hostname  and  gkrellm_theme.cfg-
              hostname files and use them instead of the normal  configuration
              files  (unless  the  --config  option is specified).   This is a
              convenience for allowing remote gkrellm independent config files
              in  a  shared home directory, and for the hostname to show up in
              the X title for window management.  This option has no effect in
              client mode.

       -s, --server hostname
              Run  in  client mode by connecting to and collecting data from a
              gkrellmd server on hostname

       -P, --port server_port
              Use server_port for the gkrellmd server connection.

       -l, --logfile path
              Enable sending error and debugging messages to a log file.

       -nc    No config mode.  The config menu is blocked so no config changes
              can  be  made.   Useful  in  certain  environments, or maybe for
              running on a xdm(1) login screen or during a screensaver mode?

       -demo  Force enabling of many monitors so themers can  see  everything.
              All config saving is inhibited.

       -p, --plugin
              For  plugin  development, load the command line specified plugin
              so you can avoid  repeated  install  steps  in  the  development


       The  default  for  most charts is to automatically adjust the number of
       grid lines drawn and the resolution per grid  so  drawn  data  will  be
       nicely visible.  You may change this to fixed grids of 1-5 and/or fixed
       grid resolutions in the chart  configuration  windows.   However,  some
       combination of the auto scaling modes may give best results.

       Auto grid resolution has the following behavior.

       Auto mode sticks at peak value is not set:

              1)  If  using  auto number of grids, set the resolution per grid
              and the number of grids to optimize the visibility of data drawn
              on  the chart.  Try to keep the number of grids between 1 and 7.

              2) If using a fixed number of grids, set the resolution per grid
              to the smallest value that draws data without clipping.

       Auto mode sticks at peak value is set:

              1)  If  using  auto number of grids, set the resolution per grid
              such that drawing the peak value encountered  would  require  at
              least 5 grids.

              2) If using a fixed number of grids, set the resolution per grid
              such that the peak value  encountered  could  be  drawn  without
              clipping.  This means the resolution per grid never decreases.

       All  resolution  per  grid values are constrained to a set of values in
       either a 1, 2, 5 sequence or a 1, 1.5, 2, 3, 5, 7 sequence.  If you set
       Auto  mode  sticks  at  peak  value  a manual Auto mode recalibrate may
       occasionally be required if the chart data has a wide dynamic range.

   CPU Monitor
       Data is plotted as  a  percentage.   In  auto  number  of  grids  mode,
       resolution  is  a  fixed  20% per grid.  In fixed number of grids mode,
       grid resolution is 100% divided by the number of grids.

   Proc Monitor
       The krell shows process forks with a full scale value of 10 forks.  The
       chart has a resolution of 10 forks/sec per grid in auto number of grids
       mode and 50 forks/second maximum on the chart in fixed number of  grids
       mode.   The  process  load  resolution per grid is best left at 1.0 for
       auto number of grids, but can be set as high as 5 if you configure  the
       chart to have only 1 or 2 fixed grids.

   Net Monitor
       gkrellm is designed to display a chart for net interfaces which are up,
       which means they are listed  in  the  routing  table  (however,  it  is
       possible  in  some  cases  to  monitor  unrouted  interfaces).  One net
       interface may be linked to a timer button which can be used to  connect
       and disconnect from an ISP.

       The  timer  button  shows an off, standby, or on state by a distinctive
       (color or shape) icon.

       ppp    Standby state is while the modem phone line is locked while  ppp
              is  connecting, and the on state is the ppp link connected.  The
              phone line lock is determined by the existence of the modem lock
              file   /var/lock/LCK..modem,   which   assumes   pppd  is  using
              /dev/modem.   However,  if  your  pppd  setup   does   not   use
              /dev/modem, then you can configure an alternative with:

              ln  -s  /var/lock/LCK..ttySx   ~/.gkrellm2/LCK..modem

              where  ttySx  is the tty device your modem does use.  The ppp on
              state is detected by the existence of /var/run/ and  the
              time stamp of this file is the base for the on line time.

       ippp   The  timer  button  standby  state  is  not  applicable  to ISDN
              interfaces that are always routed. The on state is ISDN on  line
              while  the ippp interface is routed.  The on line timer is reset
              at transitions from ISDN hangup state to on line state.

       For both ppp and ippp  timer  button  links,  the  panel  area  of  the
       interface  is  always shown and the chart appears when the interface is
       routed with the phone link connected or on line.

       If the timer button is not linked to a net interface, then  it  can  be
       used as a push on / push off timer

       Net  monitors  can have a label so that the interface can be associated
       with the identity of the other end of the connection.  This  is  useful
       if  you  have  several  net  connections or run multiple remote gkrellm
       programs.  It can be easier to keep track of who is connected to who.

   Mem and Swap Monitor
       Here you are reading a ratio of total used  to  total  available.   The
       amount  of  memory  used  indicated by the memory monitor is actually a
       calculated "used" memory.  If you enter the "free"  command,  you  will
       see  that  most of your memory is almost always used because the kernel
       uses large amounts for buffers and cache.  Since the kernel can free  a
       lot  of  this  memory as user process demand for memory goes up, a more
       realistic reading of memory in  use  is  obtained  by  subtracting  the
       buffers and cached memory from the kernel reported used.  This is shown
       in the free command output in the  "-/+  buffers/cache"  line  where  a
       calculated  used  amount  has buffers and cached memory subtracted from
       the kernel reported used memory, and a calculated free amount  has  the
       buffers and cached memory added in.

       While  the  memory meter always shows the calculated "used" memory, the
       raw memory values total, shared, buffered, and cached may be optionally
       displayed in the memory panel by entering an appropriate format display
       string in the config.

       Units:  All memory values have units of binary megabytes (MiB).  Memory
       sizes  have  historically  been  reported in these units because memory
       arrays on silicon have always increased in size by multiples of 2.  Add
       an  address  line  to  a  memory  chip  and  you double or quadruple (a
       multiplexed address) the memory size.  A binary  megabyte  is  2^20  or
       1048576.   Contrast  this  with  units  for  other  stats  such as disk
       capacities or net transfer rates where the  proper  units  are  decimal
       megabytes  or  kilobytes.   Disk  drive  capacities  do not increase by
       powers of 2 and manufacturers do not use binary  units  when  reporting
       their  sizes.   However,  some  of  you may prefer to see a binary disk
       drive capacity reported, so it is available as an option.

   Internet Monitor
       Displays TCP port connections and records historical  port  hits  on  a
       minute or hourly chart.  Middle button click on an inet chart to toggle
       between the minute and hourly displays.  There is  a  strip  below  the
       minute  or  hour  charts  where marks are drawn for port hits in second
       intervals.  Each inet krell also shows port  hits  with  a  full  scale
       range of 5 hits.  The left button toggle of extra info displays current
       port connections.

       For each internet monitor you can specify two labeled datasets with one
       or  two  ports  for  each  dataset.   There  are two ports because some
       internet ports are related and you might  want  to  group  them  -  for
       example,  the  standard  HTTP  port  is 80, but there is also a www web
       caching service on port 8080.  So it makes sense to have a HTTP monitor
       which  combines  data from both ports.  A possible common configuration
       would be to create one inet monitor that monitors HTTP hits plotted  in
       one  color  and FTP hits in another.  To do this, setup in the Internet
       configuration tab:

              HTTP  80 8080    FTP  21

       Or you could create separate monitors for HTTP and FTP.  Other monitors
       might be SMTP on port 25 or NNTP on port 119.

       If  you  check  the  "Port0 - Port1 is a range" button, then all of the
       ports between the two entries will be monitored.   Clicking  the  small
       button  on  the  Inet panels will pop up a window listing the currently
       connected port numbers and the host that is connected to it.

       gkrellm samples TCP port activity once per second, so  it  is  possible
       for port hits lasting less than a second to be missed.

   File System Monitor
       File  system  mount points can be selected to be monitored with a meter
       that shows  the  ratio  of  blocks  used  to  total  blocks  available.
       Mounting commands can be enabled for mount points in one of two ways:

       If  a  mount  point is in your /etc/fstab and you have mount permission
       then mount(8) and umount(8) commands can be enabled  and  executed  for
       that  mount  point  simply by checking the "Enable /etc/fstab mounting"
       option.  Mount table entries in /etc/fstab  must  have  the  "user"  or
       "owner"  option  set  to grant this permission unless gkrellm is run as
       root.  For example, if you run gkrellm as a normal user and you want to
       be able to mount your floppy, your /etc/fstab could have either of:

              /dev/fd0 /mnt/floppy  ext2 user,noauto,rw,exec  0  0
              /dev/fd0 /mnt/floppy  ext2 user,defaults  0  0

       If  gkrellm is run as root or if you have sudo(1) permission to run the
       mount(8) commands, then a custom mount command can be entered into  the
       "mount command" entry box.  A umount(8) command must also be entered if
       you choose this method.  Example mount and umount entries using sudo:

              sudo /bin/mount -t msdos /dev/fd0 /mnt/A
              sudo /bin/umount /mnt/A

       Notes: the mount point specified in a custom mount command  (/mnt/A  in
       this  example)  must be the same as entered in the "Mount Point" entry.
       Also, you should have the NOPASSWD option set in /etc/sudoers for this.

       File  system  monitors  can  be  created as primary (always visible) or
       secondary which can be hidden and then shown when they are of interest.
       For  example,  you  might  make  primary file system monitors for root,
       home, or user so they  will  be  always  visible,  but  make  secondary
       monitors  for  less  frequently  used mount points such as floppy, zip,
       backup partitions,  foreign  file  system  types,  etc.   Secondary  FS
       monitors  can  also  be  configured  to  always  be visible if they are
       mounted by checking the "Show if mounted" option.   Using this  feature
       you can show the secondary group, mount a file system, and have that FS
       monitor remain visible even when the  secondary  group  is  hidden.   A
       standard  cdrom mount will show as 100% full but a monitor for it could
       be  created  with  mounting  enabled  just  to  have  the  mount/umount

       When  the  "Ejectable"  option  is selected for a file system, an eject
       button will appear when the mouse enters the file system panel.  If you
       are  not  using  /etc/fstab  mounting, a device file to eject will also
       need to be entered.  Systems may have varying  levels  of  support  for
       this  feature  ranging  from  none  or  basic  using an ioctl() to full
       support using an eject command to  eject  all  its  supported  devices.
       Linux  and  NetBSD  use  the  "eject"  command  while  FreeBSD uses the
       "cdcontrol" command, so be sure these  commands  are  installed.   Most
       eject commands will also support closing a CDROM tray.  If they do, you
       will be able to access  this  function  by  right  clicking  the  eject

   Mail Monitor
       Checks your mailboxes for unread mail. A mail reading program (MUA) can
       be executed with a left mouse click on the mail monitor  panel  button,
       and  a  mail  notify (play a sound) program such as esdplay or artsplay
       can be executed whenever the new mail count increases.  The mail  panel
       envelope  decal may also be clicked to force an immediate mail check at
       any time.

       gkrellm is capable of checking mail from local mailbox types mbox,  MH,
       and maildir,  and from remote mailbox types POP3 and IMAP.

       POP3  and  IMAP checking can use non-standard port numbers and password
       authentication  protocols  APOP  (for  POP3  only)  or  CRAM-MD5.    If
       supported  by  the  mail server, emote checking may be done over an SSL
       connection if the "Use SSL" option is selected.

       Before internal POP3 and IMAP checking  was  added,  an  external  mail
       fetch/check  program  could  be  set  up to be executed periodically to
       download or check remote POP3 or  IMAP  mail.   This  method  is  still
       available  and  must be used if you want gkrellm to be able to download
       remote mail to local mailboxes because the builtin  checking  functions
       cannot download.

   Battery Monitor
       This  meter will be available if a battery exists and will show battery
       percentage life remaining.  A decal indicates if AC line  is  connected
       or  if the battery is in use.  If the data is available, time remaining
       may be displayed as well as the percentage battery level. If  the  time
       remaining  is  not available or is inaccurate, the Estimate Time option
       may be selected to display a battery time to  run  or  time  to  charge
       which  is  calculated  based on the current battery percent level, user
       supplied typical battery times,  and  a  default  linear  extrapolation
       model.  For charging, an exponential charge model may be selected.

       A  battery  low  level  warning and alarm alert may be set.  If battery
       time is not available from the OS and the estimate  time  mode  is  not
       set,  the  alert  units  will  be battery percent level.  Otherwise the
       alert units will be battery time left in minutes.  If OS  battery  time
       is  not  available  and the estimate time mode is set when the alert is
       created, the alert will have units of time  left  in  minutes  and  the
       alert  will  automatically  be destroyed if the estimate time option is
       subsequently turned off.

       If the OS reports multiple batteries, the alert will be a master  alert
       which is duplicated for each battery.

   CPU/Motherboard Sensors - Temperature, Voltages, and Fan RPM
       Sensor  monitoring on Linux requires that either lm_sensors modules are
       installed in your running kernel, that you run a  kernel  >=  2.6  with
       sysfs sensors configured, or, for i386 architectures, that you have the
       mbmon daemon running when gkrellm is started (as long as mbmon supports
       reporting sensor values for your motherboard).

       For  lm_sensors  to  be  used, gkrellm must be compiled with libsensors
       support.  It will be if the libsensors development package is installed
       when gkrellm is compiled.

       If the mbmon daemon is used, it must be started before gkrellm like so:

              mbmon -r -P port-number

       where the given "port-number"  must  be  configured  to  match  in  the
       gkrellm  Sensors->Options  config.   If you have mbmon installed from a
       distribution package, you can probably easily set up for  mbmon  to  be
       started  at  boot.   With  Debian, for example, you would edit the file
       /etc/default/mbmon to set:


       and you would need to set in the  gkrellm  Sensors->Option  config  the
       mbmon  port  to be "411" to match the default in the /etc/default/mbmon

       Sensor temperatures can  also  be  read  from  /proc/acpi/thermal_zone,
       /proc/acpi/thermal,   /proc/acpi/ibm,   the  PowerMac  Windfarm  /sysfs
       interface, and PowerMac PMU /sysfs based sensors.

       When using lm_sensors, libsensors will be used  if  available,  but  if
       libsensors is not linked into the program, the sensor data will be read
       directly from the /sysfs or /proc file systems.   If  running  a  newer
       Linux  kernel  sensor  module  not  yet  supported  by  libsensors  and
       libsensors is linked, there will also  be  an  automatic   fallback  to
       using  /sysfs as long as libsensors doesn’t detect any sensors.  But if
       it does detect some sensors which does not include the new sensors  you
       need, you can force getting /sysfs sensor data either by running:

              gkrellm --without-libsensors

       or by rebuilding with:

              make without-libsensors=yes

       Disk  temperatures may also be monitored if you have the hddtemp daemon
       running when gkrellm is started.  gkrellm uses the default hddtemp port
       of  7634.   Like  mbmon,  hddtemp  is  best started in a boot script to
       guarantee it will be running when gkrellm is started.

       NVIDIA graphics card GPU temperatures may  also  be  monitored  if  the
       nvidia-settings  command is installed and your Nvidia card supports the
       temperature reporting.  If nvidia-settings is not installed or does not
       report  temperatures  for  your  card,  an option for using the nvclock
       program will  appear  in  the  Sensors  config.   Nvclock  use  is  not
       automatically  enabled  as  is  nvidia-settings because nvclock can add
       seconds of gkrellm startup time when used on a NVIDIA  GPU  chipset  it
       does  not  support.  GKrellM must be restarted to recognize changes for
       the nvclock option.

       Requires a MBM install:

       Builtin sensor reporting is available for some sensor  chips.   FreeBSD
       systems can also read sensor data from the mbmon daemon as described in
       the Linux section above.

       Builtin sensor reporting is available for some  sensor  chips.   NetBSD
       uses  the  envsys(4)  interface  and  sensors  reading is automatically
       enabled if you have either a lm(4) or viaenv(4) chip configured in your

       General Setup:
       Temperature  and  fan  sensor displays may be optionally located on the
       CPU or Proc panels to save  some  vertical  space  while  voltages  are
       always  displayed  on their own panel.  If you set up to monitor both a
       temperature and a fan on a single  CPU  or  Proc  panel,  they  can  be
       displayed  optionally  as  an alternating single display or as separate
       displays.  If separate, the fan display will replace the  panel  label.
       The configuration for this is under the CPU and Proc config pages.

       If not using libsensors, in the Setup page for the Sensors config enter
       any correction factors and offsets for each  of  the  sensors  you  are
       monitoring (see below and lm_sensor documentation).  For Linux, default
       values are automatically provided for many sensor chips.

       But if using libsenors, it is not possible to enter correction  factors
       and offsets on the Sensors config page because libsensors configuration
       is done in the /etc/sensors.conf file.  To get sensor debug output  and
       to find out the sensor data source, run:

              gkrellm -d 0x80

       Note for NetBSD users:
              The  current  implementation  of the sensor reading under NetBSD
              opens /dev/sysmon and never closes it. Since  that  device  does
              not  support concurrent accesses, you won’t be able to run other
              apps such as envstat(8) while GKrellM is  running.   This  might
              change if this happens to be an issue.

              The  reasons  for this choice are a) efficiency (though it might
              be possible to open/close /dev/sysmon each  time  a  reading  is
              needed  without  major  performance  issue) and b) as of October
              2001, there’s a bug in  the  envsys(4)  driver  which  sometimes
              causes  deadlocks  when  processes  try to access simultaneously
              /dev/sysmon   (see  NetBSD  PR#14368).  A  (quick   and   dirty)
              workaround for this is to monopolize the driver :)

   CPU/Motherboard Temperatures
       Most   modern   motherboards   will  not  require  setting  temperature
       correction factors and offsets other than the defaults.   However,  for
       lm_sensors  it  is  necessary  to  have  a correct "set sensor" line in
       /etc/sensors.conf if the temperature sensor  type  is  other  than  the
       default  thermistor.   If  using  Linux sysfs sensors, this sensor type
       would be set by writing to a sysfs file.  For  example,  you  might  at
       boot set a sysfs temperature sensor type with:

              echo "2" > /sys/bus/i2c/devices/0-0290/sensor2

       On  the  other  hand,  some  older  motherboards  may  need temperature
       calibration  by  setting  a  correction  factor  and  offset  for  each
       temperature  sensor  because  of factors such as variations in physical
       thermistor contact with the CPU.  Unfortunately, this  calibration  may
       not  be  practical  or  physically  possible  because  it requires that
       somehow  you  can  get  a  real  CPU  temperature  reading.   So,   the
       calibration  discussion  which follows should probably be considered an
       academic exercise that might give you some good (or bad) ideas. If  you
       have a recent motherboard, skip the following.

       Anyway,  to do this calibration, take two real CPU temperature readings
       corresponding to two  sensor  reported  readings.    To  get  the  real
       readings,  you  can  trust  that your motherboard manufacturer has done
       this calibration and is reporting accurate temperatures in the bios, or
       you  can put a temperature probe directly on your CPU case (and this is
       where things get impractical).

       Here is a hypothetical CPU calibration procedure.  Make sure gkrellm is
       configured  with  default  factors  of  1.0  and  offsets  of  0 and is
       reporting temperatures in centigrade:

       1 ·    Power on the machine and read a real  temperature  T1  from  the
              bios  or a temperature probe.  If reading from the bios, proceed
              with booting the OS.  Now record  a  sensor  temperature  S1  as
              reported by gkrellm.

       2 ·    Change  the  room  temperature  environment (turn off your AC or
              change computer fan exhaust speed).  Now  repeat  step  1,  this
              time recording a real temperature T2 and gkrellm reported sensor
              temperature S2.

       3 ·    Now you can calculate the correction factor and offset you  need
              to enter into the Sensor configuration tab:


              s - S1     t - T1
              ------  =  ------
              S2 - S1    T2 - T1

                       T2 - T1     S2*T1 - S1*T2
              t  = s * -------  +  -------------
                       S2 - S1         S2 - S1


                        T2 - T1                S2*T1 - S1*T2
              factor =  -------      offset =  -------------
                        S2 - S1                   S2 - S1

   Voltage Sensor Corrections
       You  need  to  read  this section only if you think the default voltage
       correction factors and offsets are incorrect.  For Linux and lm_sensors
       and sysfs sensors
        this  would  be  if gkrellm does not know about your particular sensor
       chip.  For MBM with Windows, the default values should be correct.

       Motherboard voltage measurements are made by a variety of sensor  chips
       which  are  capable of measuring a small positive voltage.  GKrellM can
       display these voltage values and can apply a correction factor, offset,
       and  for  the  negative voltages of some chips (lm80), a level shifting
       reference voltage to the displayed voltage.  There are  four  cases  to

       1 ·    Low  valued  positive  voltages may be directly connected to the
              input pins of the sensor chip and therefore need no  correction.
              For  these,  the  correction factor should be 1.0 and the offset
              should be 0.

       2 ·    Higher valued positive voltages will be connected to  the  input
              pins  of  the  sensor  chip  through  a  2  resistor attenuation
              circuit.  For these, the correction factor will be  a  ratio  of
              the resistor values and the offset will be 0.

       3 ·    Negative  voltages  will  be  connected to the input pins of the
              sensor through a 2 resistor attenuation circuit with one of  the
              resistors  connected  to  a positive voltage to effect a voltage
              level shift.  For these (lm80), the correction factor and offset
              will  be  ratios of the resistor values, and a reference voltage
              must be used.

       4 ·    Some sensor chips (w83782, lm78) are designed to handle negative
              inputs  without  requiring  an  input  resistor  connected  to a
              voltage reference.  For these, there will be a correction factor
              and a possible offset.

              For cases 2 and 3, the sensor chip input network looks like:

                  Vs o----/\/\/---o-------------o Vin
                           R1     |
                                  o--/\/\/--o Vref


              Vs     is the motherboard voltage under measurement

              Vin    is  the  voltage  at the input pin of the sensor chip and
                     therefore  is  the  voltage  reading   that   will   need

              Vref   is  a level shifting voltage reference.  For case 2, Vref
                     is ground or zero.  For case 3, Vref will be one  of  the
                     positive motherboard voltages.

       The  problem  then  is  to  compute correction factors and offsets as a
       function  of  R1  and  R2  so  that  GKrellM  can  display  a  computed
       motherboard voltage Vs as a function of a measured voltage Vin.

       Since  sensor chip input pins are high impedance, current into the pins
       may be assumed to be zero.  In that case, the current through R1 equals
       current through R2, and we have:

                  (Vs - Vin)/R1 = (Vin - Vref)/R2

              Solving for Vs as a function of Vin:

                  Vs = Vin * (1 + R1/R2)  -  (R1/R2) * Vref

              So, the correction factor is:  1 + R1/R2
                  the correction offset is:  - (R1/R2)
                  Vref is specified in the config separately from
                  the offset (for chips that need it).

       Fortunately  there  seems  to be a standard set of resistor values used
       for the various sensor chips which  are  documented  in  the  lm_sensor
       documentation.   The  GKrellM  sensor  corrections  are  similar to the
       compute lines you  find  with  lm_sensors,  with  the  difference  that
       lm_sensors  has  an  expression  evaluator  which does not require that
       compute lines be simplified to the single factor and offset required by
       GKrellM.   But  you  can  easily  calculate the factor and offset.  For
       example, this lm_sensor compute line for a case 2 voltage:

                  compute in3 ((6.8/10)+1)*@ ,  @/((6.8/10)+1)

       yields a correction factor of ((6.8/10)+1) =  1.68  and  an  offset  of

       Note that the second compute line expression is not relevant in GKrellM
       because  there  is  never  any  need  to  invert  the  voltage  reading
       calculation.   Also,  the  compute  line  ’@’ symbol represents the Vin

       A more complicated compute line for a case 3 voltage:

                  compute in5 (160/35.7)*(@ - in0) + @, ...

              can be rewritten:

                  compute in5 (1 + 160/35.7)*@ - (160/35.7)*in0, ...

              so the correction factor is  (1 + 160/35.7) = 5.48
              and the correction offset is -(160/35.7) = -4.48
              and the voltage reference Vref is in0

       Here is a table of correction factors and offsets based on some typical
       compute line entries from /etc/sensors.conf:

                     Compute line                 Factor  Offset  Vref
              lm80   in0 (24/14.7 + 1) * @        2.633     0       -
                     in2 (22.1/30 + 1) * @        1.737     0       -
                     in3 (2.8/1.9) * @            1.474     0       -
                     in4 (160/30.1 + 1) * @       6.316     0       -
                     in5 (160/35.7)*(@-in0) + @   5.482    -4.482  in0
                     in6 (36/16.2)*(@-in0) + @    3.222    -2.222  in0

              LM78   in3 ((6.8/10)+1)*@           1.68      0       -
                     in4 ((28/10)+1)*@            3.8       0       -
                     in5 -(210/60.4)*@           -3.477     0       -
                     in6 -(90.9/60.4)*@          -1.505     0       -

              w83782 in5 (5.14 * @) - 14.91       5.14    -14.91    -
                     in6 (3.14 * @) -  7.71       3.14     -7.71    -

   Command launching
       Many  monitors  can be set up to launch a command when you click on the
       monitor label.  When a command is configured for a monitor,  its  label
       is  converted into a button which becomes visible when the mouse enters
       the panel or meter area of the label.  If  the  command  is  a  console
       command  (doesn’t  have  a  graphical user interface), then the command
       must be run in a  terminal  window  such  as  xterm,  eterm,  or  Gnome
       terminal.  For example running the "top" command would take:

       xterm -e top

       You  can  use  the command launching feature to run commands related to
       monitoring functions, or you may use it to have a convenient launch for
       any  command.   Since gkrellm is usually made sticky, you can have easy
       access to several frequently used commands from any desktop.   This  is
       intended  to  be  a  convenience  and  a way to maximize utilization of
       screen real estate and not a replacement for more full featured command
       launching  from  desktops  such as Gnome or KDE or others.  Some launch
       ideas for some monitors could be:

              gnomecal, evolution, or ical

       CPU:   xterm -e top or gps or gtop

       inet:  gftp or xterm -e ftpwho

       net:   mozilla, galeon, skipstone, or xterm -e slrn -C-
       And so on... Tooltips can be set up for these commands.

       Most monitors can have alerts configured to give  warnings  and  alarms
       for  data  readings  which range outside of configurable limits.  Where
       useful, a delay of the alert trigger can be configured.  A  warning  or
       alarm consists of an attention grabbing decal appearing and an optional
       command being executed.  For most monitors the command may contain  the
       same  substitution  variables  which  are  available for display in the
       chart or panel label format strings and are documented on configuration
       Info  pages.  Additionally, the hostname may be embedded in the command
       with the $H substitution variable.

       If you have festival installed, either a warn or alarm command could be
       configured  to  speak  something.   For example a CPU temperature alert
       warn command could just speak the current temperature with:

           sh -c "echo warning C P U is at $s degrees | esddsp festival --tts"

       Assuming you have esd running.


       A  theme  is  a  directory  containing  image  files  and  a  gkrellmrc
       configuration  file.   The  theme directory may be installed in several


       For compatibility  with  Gtk  themes,  a  gkrellm  theme  may  also  be
       installed as:


       Finally,  a theme you simply want to check out can be untarred anywhere
       and used by running:

              gkrellm -t path_to_theme

       If you are interested in writing a theme, go  to  the  Themes  page  at   and   there  you  will  find  a  Theme  making


       gkrellm tries to load all plugins (shared object files ending  in  .so)
       it finds in your plugin directory ~/.gkrellm2/plugins.  The directories
       /usr/local/lib/gkrellm2/plugins and /usr/lib/gkrellm2/plugins are  also
       searched for plugins to install.

       Some  plugins  may be available only as source files and they will have
       to be compiled before installation.  There should be  instructions  for
       doing this with each plugin that comes in source form.

       If  you  are  interested in writing a plugin, go to the Plugins page at and there you will  find  a  Plugin  programmers


       When  a  local  gkrellm  runs  in  client mode and connects to a remote
       gkrellmd server all  builtin  monitors  collect  their  data  from  the
       server.   However,  the  client gkrellm process is running on the local
       machine, so any enabled plugins will run in the local context (Flynn is
       an  exception  to  this  since it derives its data from the builtin CPU
       monitor).  Also, any command launching will run commands on  the  local


              User  gkrellm  directory  where are located configuration files,
              user’s plugins and user’s themes.

              User plugin directory.

              System wide plugin directory.

              Local plugin directory.

              User theme directory.

              User theme packaged as part of a user Gtk theme.

              System wide theme directory.

              Local theme directory.

              System wide theme packaged as part of a system wide Gtk theme.


       Bill Wilson <>.


       fstab(5), sudo(1), mount(8), pppd(8), umount(8)