QUEUEDEFS(4)QUEUEDEFS(4)NAMEqueuedefs - queue description file for at, batch, and cron
SYNOPSIS
/etc/cron.d/queuedefs
DESCRIPTION
The queuedefs file describes the characteristics of the queues managed
by cron(1M). Each non-comment line in this file describes one queue.
The format of the lines are as follows:
q.[njobj][nicen][nwaitw]
The fields in this line are:
q
The name of the queue. a is the default queue for jobs started
by at(1); b is the default queue for jobs started by batch
(see at(1)); c is the default queue for jobs run from a
crontab(1) file.
njob
The maximum number of jobs that can be run simultaneously in
that queue; if more than njob jobs are ready to run, only the
first njob jobs will be run, and the others will be run as
jobs that are currently running terminate. The default value
is 100.
nice
The nice(1) value to give to all jobs in that queue that are
not run with a user ID of super-user. The default value is 2.
nwait
The number of seconds to wait before rescheduling a job that
was deferred because more than njob jobs were running in that
job's queue, or because the system-wide limit of jobs execut‐
ing has been reached. The default value is 60.
Lines beginning with # are comments, and are ignored.
EXAMPLES
Example 1 A sample file.
#
#
a.4j1n
b.2j2n90w
This file specifies that the a queue, for at jobs, can have up to 4
jobs running simultaneously; those jobs will be run with a nice value
of 1. As no nwait value was given, if a job cannot be run because too
many other jobs are running cron will wait 60 seconds before trying
again to run it.
The b queue, for batch(1) jobs, can have up to 2 jobs running simulta‐
neously; those jobs will be run with a nice(1) value of 2. If a job
cannot be run because too many other jobs are running, cron(1M) will
wait 90 seconds before trying again to run it. All other queues can
have up to 100 jobs running simultaneously; they will be run with a
nice value of 2, and if a job cannot be run because too many other jobs
are running cron will wait 60 seconds before trying again to run it.
FILES
/etc/cron.d/queuedefs
queue description file for at, batch, and
cron.
SEE ALSOat(1), crontab(1), nice(1), cron(1M)
Mar 1, 1994 QUEUEDEFS(4)
