IDNA encoding of hostname

[Glandos]

• uvloop version: 0.8.0
• Python version: 3.5
• Platform: Debian GNU/Linux testing
• Can you reproduce the bug with PYTHONASYNCIODEBUG in env?: I don't know

Commit 1d5ae0b introduces IDNA encoding. While this is a good solution for FQDN hostnames, this is really a performance killer when sending a lot of small packets using lots of IP address (use case in boramalper/magnetico#92). On my CPU, the IDNA encoding is taking ~5% of the whole program execution, and more than 75% of the sendto method call.

The main issue here is that the sendto call is done with address given with the call to datagram_received, so uvloop should be already aware that the hostname is an IP address.
I guess that datagram_received cannot return an encoded hostname, but the idea is here.

[asvetlov]

You could skip encoding by sending host parameter as bytes, isn't it?

[Glandos]

Yes, but the host parameter is the one received from datagram_received, so it theoretically could be a FQDN.
EDIT: I don't know if there is a fast test to tell if the host is an IP address or not.

[1st1]

EDIT: I don't know if there is a fast test to tell if the host is an IP address or not.

Yes, there's a fast test. I'll look into this.

[1st1]

Fixed in master. Will be in 0.9.0 release (soon)

[1st1]

Please try uvloop v0.9.0.