I read through the justthread documentation for the jss::concurrent_map and it said that it can allow concurrent access from 200 connections. What imposes the 200 limit? Can that be increased?
The 200 accessor limit is due to the size of the required data structure. Increasing the limit will increase the size of the data structure, and in turn increase the time spent checking it during erase.
It is just a constant in the header, and could in principle be changed, or even made configurable via a macro.
Why do you need more than 200 concurrent accesses?