EBZ/CED May 99
                                QPROC

QPROC is a procedure that keeps the cron jobs from stacking up. It
allows cron jobs to run only one at a time, for up to a predetermined
amount of time (to prevent runaway processes), and it postpones any
cron job from running if the load average is 5 or above.  Qproc checks
to make sure that only one copy of a given job is in the queue -- if
you add the same job twice [with the -uniq flag], the second job
silently vanishes.  That prevents logjams from building up if something
does hang for a while.  

All mdi cron jobs run by mdisas should use qproc (except for monsci5k,
which runs semi-eternally).

Qproc maintains a daemon that does the queue processing.  When it is
time for a cron job to be run, the qproc command puts the job in the
queue and, if necessary, starts a daemon running.  All jobs in the
queue are run in order by the daemon (of course, more jobs can be
added to the queue in the meantime).  If the queue gets empty, the
daemon shuts down until it is called again by another cron job.  To kill
qproc, use the process id number and kill the daemon. However, it will
not stay down for long - as soon as it is time for a cron job to run
it will be reactivated. To shut down the cron jobs completely you must
killall cron (as root).

The qproc procedure is in /mdisw/bin/qproc

In /tmp on MDISAS are the following files
        
        mdi-crontab-queue          this is the current queue for all jobs 
                                   to be run
        mdi-crontab-queue.job      this is the list of the current job
        mdi-crontab-queue.log      this is a log of all jobs run since the last
                                     computer reboot
        mdi-crontab-queue.pid      this is the process id of qproc - use this
                                     number to kill the qproc daemon

Each line of the queue file contains the time that the job was added,
the number of seconds it is allowed to run before being killed, and the
job itself.