Looking at how the jbpm_job table is utilized, yes, I think these specific indexes can be removed. Just to clarify. From what I have seen in our use-case, under normal circumstances the jbpm_job table has very few entries at any point in time. Seems like entries are added and removed constantly. That being the case, I'm not sure I can see a benefit of spending the extra time/resources maintaining indexes which are never utilized.
I'm going to explore the possibility of removing the job indexes. Can you please create a JIRA issue for this?
By the way, this is as good a time to explain the use-case that is failing for us. We have a workflow with three steps synchronous steps. The first step takes a couple to a few hundred milliseconds to complete, the second step can take anywhere from 5 to 30 seconds to complete and then the last step usually takes a half a second. When I mentioned jobs earlier, I was referring to workflows contained the three steps just mentioned.
If possible, could you attach your workflow and test harness to the JIRA issue? Please remove any sensitive information you would not like to see published.