That is the time including all I/O and solver time -> Elapsed time. It seems that the batch solution requires much less time compared to the GUI one for the 10 iterations. The other output is not really helpful as you have done it for different number of iterations (or your time steps required completely different number of outer iterations) but does not depict huge differences.
You might use a standard case which you can then benchmark on your ressources to check if the timing you are getting are appropriate or not.
Back to your first question regarding starting, then getting slow, stopping then continuing: it is hard for me from here to debug on that.
You are navigating away from the AIS Discovery experience