Cron job running sporadically

[koenn]

yeah, I was also thinking that the 6 AM script running too long could interfere with the 1PM script starting - but shouldn't cron throw an error then ? (IIRC Ubuntu server drops those in the root mailbox)


Hunch: the 6PM script sets a lock on certain resources (eg files, or maybe database tables), the 1 PM jobs fails because the resources are still in use and it can not access them; by the next day the locks are released or have timed out so the 6AM job starts again just fine.
The timings from the COg's wrapper should indicate whether this is the case. ...

[aysiu]

Thanks, everyone, for your suggestions. I want to be as systematic as I can about this. Unfortunately, things have gotten a bit busy for me, so I haven't had a chance to properly isolate the problem yet.

[aysiu]

Right now I have it set to run once a day in the morning, and it seems to be good, so I may just stick with that for now.

[SeijiSensei]

Does the job write a log? How long does it take to complete?

[aysiu]

It just send a PHP email. Takes less than a second to complete.

[SeijiSensei]

Then it's still puzzling why you seemingly cannot run another instance of the job six hours later.

[aysiu]

I know. Haven't had the time to devote to this to properly diagnose the issue yet.