Start Process smart service

Can you give more context? What is each process doing? Why do they need to be chained? How long is it taking? 

Added to this, generally speaking Chaining will not be relevant to a Start Process SS - since it launches asynchronously the most you'd expect from this is if a user happens to chain from a prior task and into a new task (where the intermediary steps included a Start Process node); I bring this up mainly because it seems like OP might be under the mistaken impression that a user would be able to chain "into" the "Start"ed subprocess, which of course is outright incorrect.

Added to this, generally speaking Chaining will not be relevant to a Start Process SS - since it launches asynchronously the most you'd expect from this is if a user happens to chain from a prior task and into a new task (where the intermediary steps included a Start Process node); I bring this up mainly because it seems like OP might be under the mistaken impression that a user would be able to chain "into" the "Start"ed subprocess, which of course is outright incorrect.

Hi Mike, After removing the chaining it is taking the same time even.

I made no claims that removing chaining would make anything faster here.  My primary guess is that the chaining is irrelevant in the first place.

Perhaps you could post a bit more detail about what exactly you're trying to accomplish and what issue you're having with it?  I still don't understand what use case you're trying to solve here.