macOS Yosemite and above utilize AWDL (Apple Wireless Direct Link) to handle data transfers to other AWDL-enabled devices (Macs, Macbooks, iPhones, etc.) over the Wifi Radio, without the need for a common underlying Access Point.
However, whenever AWDL is active (Bonjour discovery and any Airdrop, Airplay, and GameKit links and transfers), it will lock the Wifi radio for small intervals. For Bonjour discovery specifically, this comes to an effective packet spooling time of about 50-100ms, once per second (active transfers will be higher).
Obviously, this will create unacceptable latency spikes for low-latency desktop streaming apps. To disable the AWDL interface, use the following command in Applications > Utilities > Terminal (this requires you to be logged in as an Administrator and enter your password):
sudo ifconfig awdl0 down
sudo - run as root
ifconfig - configure network interface parameters
awdl0 - the virtual interface device used for AWDL
down - disable the interface
Note that this will prevent all users on the system from using Airplay, Airdrop, GameKit, etc. To reverse, use sudo ifconfig awdl0 up.
macOS may reenable the interface upon a restart. If you want to keep it off automatically, you can write an Automator application to execute that command, then put it into your Login Items (though it will ask for your password every time). To execute it as root automatically, you may have to write a launchd daemon property XML.
Additional reading:
https://arxiv.org/abs/1808.03156
man 8 ifconfig
To a lesser extent, the Location Service Wifi scan will also lock the Wifi radio, albeit no more than around once every 5 minutes. To disable it as well:
Settings > Security & Privacy > Privacy > Location Services > Uncheck
Note that this turns off geolocation completely, including for Find My Mac.
Great toggle approach from @Kaylebor. The gap I kept hitting even with a manual one: macOS brings AWDL (Apple Wireless Direct Link) back on its own - time-based after ~10-15 min, and immediately when AirDrop/Handoff fire - so mid-session the stutter quietly returns and I had to remember to flip it again.
I attempted to that by making it automatic: a small root LaunchDaemon that re-asserts every 10 seconds. It forces
awdl0down while a flag file exists and lets it back up when the flag is gone - still a toggle that keeps AirDrop/Handoff when you're not streaming, but now I don't have to babysit:No deps (plain ifconfig + a flag check). Full script + plist + install: https://gist.github.com/artemkoloskov/453ec338cd5f31eaed29285a6a5c0cf8