Hi, ever since I updated to Big Sur, internet download speeds when tethering to my iPhone have gotten unusably slow at times. Upload speeds as far as I can tell are unaffected. I rely on hotspot tethering for my internet, and this can make video calling over my computer impossible, which as you might guess, is a huge problem.
MacBook Air 11″, macOS 11.0
Are you literally tethering (with a cable between the iPhone and the MacBook) or using the wireless hotspot function on your phone? The wired connection should be stable over time, but a wireless connection could be subject to intermittent interference.
Either way, what are the hotspot/tethering rules of your cellular carrier? Some slow those connections WAY down after a certain amount of data in a contract month or when the network gets busy.
I don't know offhand why either of those should be affected by installing Big Sur.
I’m using the wireless hotspot (iPhone XR to MacBook Air 2015). My cellular carrier allows for unlimited data and unlimited hotspot use (Taiwanese carrier). I didn’t notice any problems before updating to Big Sur—speeds were always comparable between my phone and my computer. Yesterday it was just about at its worst: speeds so slow I was receiving messages on my computer half a minute later than on my phone (sending messages from my computer was fine; online speed test showed blazing fast upload speeds), and then I restarted my computer and it was fine again. So it seems to be a computer problem. Today it’s been fine, but I expect it’ll get bad again sometime. It remains to be seen whether a restart will always fix the problem or not.
Hotspot tethering to iPhone unusably slow on Big Sur
