loadwatch(1) [debian man page]

LOADWATCH(1)						      General Commands Manual						      LOADWATCH(1)

NAME

       loadwatch - run a program when machine is idle

SYNOPSIS

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

DESCRIPTION

       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.

OPTIONS

       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).

SEE ALSO

       lw-ctl(1), nice(1)

BUGS

       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  consid-
       ered in isolation.

AUTHOR

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

								     July 2003							      LOADWATCH(1)

setpgid(2)							System Calls Manual							setpgid(2)

NAME

       setpgid(), setpgrp2() - set process group ID for job control

SYNOPSIS

DESCRIPTION

       The  and system calls cause the process specified by pid to join an existing process group or create a new process group within the session
       of the calling process.	The process group ID of the process whose process ID is pid is set to pgid.  If pid is zero, the process ID of the
       calling	process is used.  If pgid is zero, the process ID of the indicated process is used.  The process group ID of a session leader does
       not change.

       is provided for backward compatibility only.

   Security Restrictions
       Some or all of the actions associated with this system call are subject to compartmental restrictions.

       See compartments(5) for more information about compartmentalization on systems that support that feature.  Compartmental  restrictions  can
       be  overridden  if  the process possesses the privilege (COMMALLOWED).  Processes owned by the superuser may not have this privilege.  Pro-
       cesses owned by any user may have this privilege, depending on system configuration.

       See privileges(5) for more information about privileged access on systems that support fine-grained privileges.

RETURN VALUE

       and return the following values:

	      Successful completion.
	      Failure.
		     is set to indicate the error.

ERRORS

       If or fails, is set to one of the following values.

	      The value of   pid matches the process ID of a child process of the calling process and the child process has successfully  executed
			     one of the exec(2) functions.

	      The value of   pgid is less than zero or is outside the range of valid process group ID values.

	      The process indicated by
			     pid is a session leader.

	      The value of   pid  is  valid  but matches the process ID of a child process of the calling process, and the child process is not in
			     the same session as the calling process.

	      The value of   pgid does not match the process ID of the process indicated by pid and there is no process with a	process  group	ID
			     that matches the value of pgid in the same session as the calling process.

	      The value of   pid does not match the process ID of the calling process or of a child process of the calling process.

AUTHOR

       and were developed by HP and the University of California, Berkeley.

SEE ALSO

       bsdproc(3C), exec(2), exit(2), fork(2), getpid(2), kill(2), setsid(2), signal(2), privileges(5), termio(7).

STANDARDS CONFORMANCE

																	setpgid(2)