That is what I cannot tell. We have Orion 2013.1.0, NCM 7.1.1, SAM 5.5.0, NPM 10.5, IPAM 4.0, VNQM 4.0.1, NTA 3.11.0, IVIM 1.6.0 installed in the environment. I have an upgrade planned in the near future to bring us up to the latest versions of each component. But, this issue with the job engine has persisted through the last 2 upgrades.
As far as I've been able to find, the Job Engine is a black box. I can see metrics on the number of workers and jobs going through it, but no details about the job breakdowns or even how the jobs correlate to the configuration within the application. I can make some guesses about the correlation, but that doesn't help much to find any specific details on the culprit.
I can see log files piling up with what appear to be process id numbers appended, but they are of zero length, no content to be found. Since I haven't seen any others with this problem, I suspect the problem being in something custom that was written or a particular configuration issue; not necessarily a problem with the job engine directly.
Please let me know of any knowledge you have.