monitoring jobs (dbms_job)

Has anyone tried monitoring the run duration of jobs scheduled with dbms_jobs over time to determine trends? I'm thinking of running some pl/sql in intervals that will, in general, do the following: looking at jobs that are scheduled to run at least that often, note their next_date and then, when the monitored job runs next time, compared the noted next time to the values in last_date. The description of the dba_jobs view gives me doubts however, as it doesn't seem to correspond to reality in respect to last_date, last_sec columns. My observation has been that last_sec shows when the job last completed, but the view description says it shows when the job last started.

The business need is to prevent jobs from running into the scheduled cold backups and interfering with them. I've searched the archive and ask tom, but couldn't come up with any direct hits. If anyone has tried this before, I would appreciate if you could point out any non-trivial issues you've encountered, thanks.

mostly 9i's with some 8i's thrown in on solaris.

Max Pakhutkin

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