[Twisted-Python] Effects of backlog parameter on listenTCP

[Tobias Oberstein]

Could someone shortly elaborate on the semantics / effect of the parameter "backlog" with listenTCP?

The docs say: "size of the listen queue".

Is that a tunable within Twisted?

I mean, there are kernel parameters for queue sizes of not yet completely TCP handshaked connections and so on. But those are kernel tunables.

What does the "backlog" parameter?

The reason I am asking: I am stress testing a Twisted server and I see client connections denied upon high connection rates .. does the parameter help?

Thanks!
Tobias