My API Workflow on a list skips steps. What to do?

I have an API workflow that runs a list of usually 2-10 items.

The only action in that workflow is to run a 2nd API workflow that runs another list of potentially 100 items. That second workflow looks like this:

Each action in this second workflow gets skipped regularly even if I assign 10-second intervals to both workflows.

Questions:

  1. Do I need to give a huge interval like 20 minutes to the first workflow to be sure the second workflow is only running on 1 list at a time?
  2. What if 5 users trigger the first workflow at the same time? Does that cause even more problems?
  3. Is this ( Parallel actions is way faster - #6 by laurence ) a potential solution for me, @JohnMark?

Thank you!

Is the first workflow using Schedule API Workflow on a list?

Does the second workflow make changes to any of the same rows as another instance would, for example in the step Make changes to User, is the same User being updated more than once? You may find it doesn’t skip actions if each instance is completely independent.

According to @josh, for large lists, using a recursive API workflow is more reliable, presumably as it guarantees just one instance at a time.

More reliable for long lists

Yes, the 1st workflow is a list, basically a list of 2-10 users.

The 2nd workflow is on a list of numbers that dictate how many things should be created for each of those users.

And I think the real trouble is that the 1st workflow may be called, say, 5 times within 1 minute. I think that’s where the problem is - lots of overlap. Don’t know how to prevent that, though.