NAME

       pbs_sched_cc - pbs C scheduler

SYNOPSIS

       pbs_sched [-a alarm] [-d home] [-L logfile] [-p file] [-S port] [-R port] [-c file]

DESCRIPTION

       The  pbs_sched program runs in conjunction with the PBS server.  It queries the server about the state of
       PBS and communicates with pbs_resmon to  get  information  about  the  status  of  running  jobs,  memory
       available etc.  It then makes decisions as to what jobs to run.

       pbs_sched must be executed with root permission.

OPTIONS

       -a alarm       This  specifies  the  time  in  seconds to wait for a schedule run to finish.  If a script
                      takes too long to finish, an alarm signal is sent, and the scheduler is restarted.   If  a
                      core  file  does  not exist in the current directory, abort() is called and a core file is
                      generated.  The default for alarm is 180 seconds.

       -d home        This specifies the PBS home directory, PBS_HOME.  The current  working  directory  of  the
                      scheduler  is  PBS_HOME/sched_priv.   If  this  option  is not given, PBS_HOME defaults to
                      $PBS_SERVER_HOME as defined during the PBS build procedure.

       -L logfile     Specifies an absolute path name of the file to use as the log file.  If not specified, the
                      scheduler will open a file named for the current date in the PBS_HOME/sched_logs directory
                      (see the -d option).

       -p file        This specifies the "print" file.  Any output from the C code which is written to  standard
                      out or standard error will be written to this file.  If this option is not given, the file
                      used will be PBS_HOME/sched_priv/sched_out .  See the -d option.

       -S port        This specifies the port to use.  If this option is not given, the default port for the PBS
                      scheduler is used.

       -R port        This specifies the resource monitor port to use.  If this option is not given, the default
                      port  for the PBS mom is used.  NOTE: this option only makes the mom port available to the
                      scheduler writer.  It doesn't force them to use it.

       -c file        Specify a configuration file, see description below.  If this is a relative file  name  it
                      will  be  relative  to  PBS_HOME/sched_priv,  see  the -d option.  If the -c option is not
                      supplied, pbs_sched will not attempt to open a configuration file.

       The options that specify file names may be absolute or  relative.   If  they  are  relative,  their  root
       directory will be PBS_HOME/sched_priv.

USAGE

       This  version  of  the  scheduler  requires  knowledge of the C language and the PBS API.  Source code is
       provided for a main program for the scheduler.  The site must supply the  heart  of  the  program.   When
       invoked,  the  main  program  performs  general  initialization  and housekeeping chores.  Then a locally
       supplied function, schedinit() is called to perform site specific initialization.

       In the main loop, a locally supplied function, schedule() is called to make the scheduling decisions  and
       perform  any required actions.  Information about jobs and queues is obtained from the Server through the
       standard PBS API as found in libifl.a.  Information about the execution  host(s)  is  obtained  from  the
       Resource Monitor.  Routines to communicate with the Resource Monitor are found in libnet.a.

       If  the  processing  takes  more  than the allotted time, the scheduler will restart itself.  The default
       amount of time is three minutes.  This can be changed with the -a option.

       On receipt of a SIGHUP signal, the  scheduler  will  close  and  reopen  its  log  file  and  reread  its
       configuration file (if any).

CONFIGURATION FILE

       A  configuration  file  may  be specified with the -c option.  This file may be used to specify the hosts
       (servers) which are allowed to connect to pbs_sched.  The hosts are specified in the  configuration  file
       in a manor identical to that used in pbs_mom.

       clienthost
              One or more servers, one per line, may be specified:

              $clienthost    hostname +.IP restricted Allows connections from non-priviledged ports on the named
              hosts.  Typically only used with Mac OSX:

              $restricted   hostname

              Two host names are always allowed to connection to pbs_sched, "localhost" and the name returned to
              pbs_sched  by  the  system  call  gethostname().   These  names  need  not  be  specified  in  the
              configuration file.

       The configuration file must be "secure".  It must be owned by a user id and group id less than 10 and not
       be world writable.

FILES

       $PBS_SERVER_HOME/sched_priv
                 the default directory for configuration files, typically (/usr/spool/pbs)/sched_priv.

Signal Handling

       A C based scheduler will handle the following signals:

       SIGHUP The server will close and reopen its log file and reread the config file if one exists.

       SIGALRM
              If  the site supplied scheduling module exceeds the time limit, the Alarm will cause the scheduler
              to attempt to core dump and restart itself.

       SIGINT and SIGTERM
              Will result in an orderly shutdown of the scheduler.

       All other signals have the default action installed.

EXIT STATUS

       Upon normal termination, an exit status of zero is returned.

SEE ALSO

       pbs_sched_tcl(8B), pbs_server(8B), and pbs_mom(8B).
       PBS Internal Design Specification

Local                                                                                              pbs_sched(8B)