Working With AS/400 Active Jobs

Having worked on and administered IBMs midrange AS/400, iSeries and System i platforms for the better part of ten years I have found that you can boil down the essential administrative functions to a few select commands available from one primary command. Let me explain.



One of the major functions of the platform is the concept of work management using jobs and subsystems. Everything that runs on the good old 400 is considered a job; now some jobs run interactively like your green screen logins and the rest of them run in batch type environments.



So when it comes to monitoring the performance of the system at any given time you will want to become familiar with the Work With Active Jobs command WRKACTJOB. The command displays all of the jobs presently operating and under which subsystem it is running under. It also shows some vital information related to the job like CPU usage.



Now a really key point that everyone seems to be confused over is whether to use the F5 or F10 keys to refresh the information and datat displayed on the screen. I have seen people do it incorrectly so let's examine what each of those keys do.

First of all F5 refreshes the information on the screen like the CPU % used but it does not reset the statistics. So it just adds it to the running total, you can see the time period for the running total by looking at the "elapsed time" counter at the top center of the screen underneath the display title.



When you press the F10 key it restarts the statistics and displays then since the last time the screen was displayed. So if you wanted to track a specific jobs resource usage over a small period of time you would press F10 to reset the screen statistics and then F5 to update the information. Once finished simply press F10 again to reset those counters.



Other very handy options include the ability to do a display job log by taking option 5 for display which then calls the command Work with Job or WRKJOB. From the WRKJOB screen simply take option 10 and press the F10 to display the entire job log for that job. This is very usefull for debugging purposes or figuring out why a message occurred for a given job.



If you need to see any spool files or printed output that a job has created simply take option 8 from the WRKACTJOB screen. I find this option very useful to see if a job has created a report or other spooled file that may have already printed which is indicated by the status field. This is much more useful then searching through output queues or using the Work With all Spool files command WRKSPLF to find out if a reported has been generated.



Finally you will want to be familiar with using option 4 for ending a job. You will at some point or another find a job stuck in a loop, a user created query taking up all the resources or just needing to log a users interactive sessions off the system. This is what option four is all about by calling up the End Job command ENDJOB.



You will notice that each of the additional job commands available from the Work With Active jobs screen are available as standalone commands, however to use them separately requires knowing the job name, user and the unique job number. I find it is much faster just to pop into WRKACTJOB look at a job log or another function since it passes the name, user and job number into the specific commands automatically.