Browse Prior Art Database

Asynchronous Print Job Scheduler

IP.com Disclosure Number: IPCOM000110340D
Original Publication Date: 1992-Nov-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 3 page(s) / 121K

Publishing Venue

IBM

Related People

Lahey, LC: AUTHOR [+2]

Abstract

Disclosed is a Print Job Scheduler design that allows the Spooler process, the Print Job Scheduler process (and datastream Converter) and the Print Driver process to run asynchronously, which maximizes system printing performance.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Asynchronous Print Job Scheduler

       Disclosed is a Print Job Scheduler design that allows the
Spooler process, the Print Job Scheduler process (and datastream
Converter) and the Print Driver process to run asynchronously, which
maximizes system printing performance.

      This design uses a Job Record Queue to keep the printer
supplied with print jobs.  Each Job Record in the Job Record Queue
contains enough information about the print job for it to be printed
correctly.  The Job Record includes such information as the path/file
name of the print file, print profile parameters associated with the
job, etc.

      The Spooler simply feeds the available jobs to the Job Record
Queue.  These jobs are placed at the back of the Job Record Queue, as
illustrated in the figure.  The Spooler must indicate to the user
that these jobs have been submitted for printing.  The Spooler
receives the status of the individual print jobs asynchronously via
the Job Return Queue from the Job Scheduler, as the Job Scheduler
receives information about what pages are stacked in the printer via
the Print Driver and the Converter.  When this status is received,
the Spooler can change the job status as appropriate, and perform any
post-printing operations necessary (such as deleting the spool files
associated with jobs that printed successfully).

      The Job Scheduler takes Job Records off the front of the Job
Record Queue, schedules the job pieces (Header page, user document,
Trailer page, etc.) and sends them to the Converter for datastream
conversion.  The converted datastream is sent to the Print Driver as
it is converted, but the printer is running behind the Converter
(since it cannot print as fast as the Converter can convert).  Any
errors at the printer are returned to the Job Scheduler
(synchronously via the Print Driver and the Converter), which may
cause the Job Scheduler to back up in the datastream, possibly to a
page in a previous print job.  If this occurs, the Job Scheduler must
place the job record(s) back on the front of the Job Record Queue in
the reverse order...