Curiosity-Driven Inquiry: Why a Global Map for Socket Management

[FreeYourSoul]

Hello,

When a large number of sockets are instantiated and accessed across multiple threads, each message sent (via any function in the nng_send family) triggers a lookup in a global map that is protected by a mutex. Doesn't this create a potential point of contention? Are there benchmarks available that demonstrate this overhead is negligible, or is it simply that using many sockets is not recommended—in favor of utilizing Scalability Protocols, which are intended to eliminate the need for numerous sockets?

Overall, I'm curious about the rationale behind this design decision: why employ a global map instead of transferring the responsibility of managing socket lifetimes to the library user?

Thank you.