what about mosca's performance?

[tennessine]

how many connections can it hold.

[mcollina]

It basically depends on the RAM. On an AWS large instance it can reach 10k
concurrent connections, with roughly 10k messages/second.

I did this testing some time ago, so these figures might have changed.

Matteo

[tennessine]

can it deal with offline message ? I mean pub users published message when sub users do not online.how to deal with that

[mcollina]

the performance of offline messaging mainly depends on the used database. With LevelDB there is almost no performance overhead.

Have a look at: http://mcollina.github.io/mqtt_and_nodejs/#14