Ubuntu 16.04: Wireless / WiFi is slow

Ubuntu has notoriously buggy Wireless / WiFi drivers. The most typical cause of slow wireless is Ubuntu’s 802.11n driver. Disabling this drive resolves the problem.

Temporary fix (not preserved between reboots):

sudo modprobe -r iwlwifi
sudo modprobe iwlwifi 11n_disable=1

Now, run speed test. If issue is resolved, do the “Permanent Fix.”

Permanent fix:

echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf