Hi,

What version of NA are you using?  

I've seen this in the past but was quite some time ago (10.x version).  I as able to improve this a bit with how my script was written, but there was still a difference (slower).

So, question, have you seen any issues if you run the same task in the Web UI?  Is it all tasks?  By chance, are you doing a run external application?  

This may not be the easiest thing to do, but find a time when not much else is running on NA, then for troubleshooting, turn up / set to trace

api/cli

system/db

system/query

system/scheduler

and then repeat your test

then reset the logging and collect the troubleshoot.zip and see if you notice anything odd.  

You should see your connection, the commands issued and then the scheduler (and DB) actions.  Just curious if you see any errors or similar with scheduler.  

Good luck!