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       loadwatch - run a program when machine is idle


       loadwatch [options] -p pid | [--] prog [args]


       loadwatch  either  spawns  a child process prog with the arguments args
       and controls it with all its process group,  or  takes  control  of  an
       already running process with pid pid with all its process group.

       loadwatch allows the controlled processes to run while the load average
       remains below high_limit. Every delay  seconds,  loadwatch  checks  the
       load  average. If the load is above high_limit, the child is suspended;
       the child is resumed when the load falls below low_limit.


       A summary of options is included below.

       -h high_limit
              A decimal value that sets the system load  at  which  the  child
              process will be suspended. (Default: 1.25)

       -l low_limit
              A  decimal  value  that  sets the system load at which the child
              process will be resumed. (Default: 0.25)

       -d delay
              An integral number of seconds that sets  how  often  the  system
              load will be checked. (Default: 10)

       -n copies
              An  integer value that sets the number of copies of prog to run.
              (Default: 1)

       -u file
              Create a UNIX domain socket file for use by lw-ctl.

       -p pid The pid of the program that should be  controlled  by  loadwatch
              (with all its process group).


       lw-ctl(1), nice(1)


       You  should  choose  low_limit  and high_limit carefully. When the load
       drops below low_limit, the process(es) will be resumed, and  it  should
       not,  by itself, cause the load to raise above high_limit, or the whole
       will oscillate, periodically suspending and resuming the process(es).

       Similarly, if several instances of  loadwatch  are  running,  they  may
       resume their processes at the same time, leading to oscillations if the
       limits are not carefully chosen.  Hence,  each  instance  of  loadwatch
       affects  every  other  instance  on  the  computer,  and  should not be
       considered in isolation.


       This manual page was written by Dale  E.  Martin  <>,
       for  the  Debian  GNU/Linux  system (but may be used by others). It was
       then updated by Nicolas Boullis <>.

                                   July 2003