SocketIO Connection Time.

[AhmMhd]

Hey, I am writing this question just for curiosity.
So, I am using Socket.IO in one of my projects (Android App), and we have to start and keep the socket connection alive on shallow networks (ex: 30-40kbps). I have observed that Socket.IO connection is not guaranteed in such networks, sometimes it connects and sometimes it does not.
So from a POC point of view, I have tried native WebSocket from OKHTTP to observe the behaviour and it turned out to be the same in terms of connection. However, I have observed the WebSocket connections were established slightly faster than socket.io.
For example, Socket.IO is taking approximately 13-15 seconds to start the connection in a 40kbps network and on the other hand, WebSocket was able to start the connection in 10-12 seconds. similarly, in every network, the WebSocket connection was slightly faster than socket.io.
2-3 seconds faster connection time might not be much for everyone but it certainly is for my use-case.

I am curious that if socket.io is built on top of WebSocket then why is it taking more time to establish the connection?
and is there any way I can improve the connection performance in Socket.IO to match WebSocket?