Polling modbus TCP about modbus

[mhemeryck]

From looking the code (e.g. https://github.com/goburrow/modbus/blob/606c02f4eef527a1d4cf7d8733d5fd7ba34f91d8/tcpclient.go), the connection only closes after a time-out of 60s, so I assume it's not really required to manage the TCP connection any other way for my purpose, right?

[nguyenthenguyen]

@mhemeryck You no need manage TCP connection. Connection closed when Close method called or after timeout when not have any activity by flag mb.lastActivity

[mhemeryck]

Thanks for the quick feedback, this confirms what I found there 👍

That's actually nice, since it means I don't need to do any management on the TCP connection level. I would only need to make sure I would re-use the same client -- which I am already doing. I could perhaps find some speed-up in having multiple clients each doing their own polling (but then the server would need to be able to keep with that as well).

For the rest I guess I will need to do a more proper time profiling in my own package to see how I can further increase the reaction time.

[mhemeryck]

Just noticed this ticket was still open; my question was pretty much answered by now.

For my setup, I did end up having each of my groups of coils to be polled have their own client instance. I still think it's probably not that "pretty", but as the client manages the connection itself, it makes sense I suppose.