[Python-Dev] socket.create_connection slow

"Martin v. Löwis" martin at v.loewis.de
Thu Jan 15 19:06:58 CET 2009

> Right, there is no way to try to simultaneously connect using ipv4
> and ipv6, apparently.

Ah, I see what you meant. No, this cannot work - what if you get
positive ACKs on both protocols?

> Also, the problem with setting the registry TcpConnectMaxRetries
> registry entry is that it also affects retries wen no ACK is
> received.  This is probably something one doesn't want to mess with.

Indeed. They were wrong to overload this setting.

> Okay, so do we want to bug MS about this? 

If you think it helps, go ahead! This has been in the system for so
long that they are unlikely to change it. Yet, as IPv6 deployment
progresses, this case will occur more and more often (until eventually
all services are dual-stacked - in which case the only effect will be
that you wait 2 seconds if the service is really not available; 1s
delay per protocol).

If the default retry counter can't be changed, I'd suggest that they
provide a socket option.


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