How to find out how many threads of transactions Spectrum Geotax can handle

Product Feature: GeoTAX Subscription Database
The limit to how many request Spectrum will queue is 65535 - number of used ports.  

After that, there are just not any more sockets to use.

But how many concurrent requests can be processed is a function of the size of the pool for the database resource.
UPDATED:  October 20, 2017