queuedefs(F) 19 June 1992 queuedefs(F) Name queuedefs - scheduling information for cron queues Description The queuedefs file is read by the clock daemon, cron, and controls how jobs submitted with at, batch, and crontab are executed. Every job sub- mitted by one of these programs is placed in a certain queue, and the behavior of these queues is defined in /usr/lib/cron/queuedefs. Queues are designated by a single, lower-case letter. The following queues have special significance: a at queue b batch queue c cron queue For a given queue, the queuedefs file specifies the maximum number of jobs that may be executing at one time (njobs), the priority at which jobs will execute (nice), and the how long cron will wait between attempts to run a job (wait). If njobs jobs are already running in a given queue when a new job is scheduled to begin execution, cron will reschedule the job to execute wait seconds later. A typical file might look like this: a.4j1n b.2j2n90w Each line gives parameters for one queue. The line must begin with a letter designating a queue, followed by a period (.). This is followed by the numeric values for njobs, nice, and wait, followed by the letters j, n, and w respectively. The values must appear in this order, although a value and its corresponding letter may be omitted entirely, in which case a default value is used. The default values are njobs = 100, nice = 2, and wait = 60. The value for nice is added to the default priority of the job (a higher numerical priority results in a lower scheduling priority - see nice(C)). wait is given in seconds. File /usr/lib/cron/queuedefs queuedefs file