[arch-general] Unstable/Unusably slow Wi-Fi connection with systemd-networkd/wpa_supplicant

[riveravaldez]

Hi, I was using Wicd until a couple of weeks without problems,
but because it's been out of repos for a while and generally not
maintained/developed anymore I decided to make the switch and
start using systemd-networkd.
The machine is a laptop Dell XPS 15 L502X (Sandy Bridge) with:

03:00.0 Network controller: Intel Corporation Centrino Wireless-N 1030
[Rainbow Peak] (rev 34)

I followed the Arch Wiki without problems and wired connection
seems to be working flawlessly. But Wi-Fi is unstable and slow
at the point of unusability.

I posted on the forums[0] for help but didn't get any until now, so
I'm letting the link here just in case someone can give me any hint.
In the forum's post I informed the output of terminal, networkctl and
wpa_cli status, dmesg, journalctl, etc.

Please let me know if I should put the details here (didn't did it just
to not make mail extremely long, hope I'm not doing wrong) or add
anything else.

Thanks a lot in advance. Best regards.

[0] https://bbs.archlinux.org/viewtopic.php?id=264608