I've been having trouble since the start of today's sessions with zoom and streaming in general on my Mac. As soon as the streaming starts, my kernel_start process goes up to more than 1000% and the Mac gets stuck. Everything is totally slow and I have to restart my Mac. Is there someone having the same problem?
Is it just my problem?
I'm sorry in this situation I won't be able to deliver my talk.
I'm so sorry you couldn't deliver your talk, @s_federici 
I've had Zoom use 200% of my CPU on Linux, but only eventually.
I have to understand what is happening to my Mac. It is pretty new (less than one year), 64GB of memory, 4 TB of disk. Until June everything was running smoothly. Then Chrome slowed down, so I upgraded from Catalina to BigSur. Then everything started working really bad. I thought I had discovered that the solution was not using Chrome at all (or just using at most one tab) -not ideal admittedly. But then, a bit yesterday, and a lot today, using Zoom everything went really bad. I hope I can keep using my new Mac instead of having to go back to Windows (that I used for 20 years; not ideal, but never had this kind of dramatic problems).
Aside from the domain name being its own statement, you might take a look at the keystone app installed with chrome: http://chromeisbad.com
Imho, it's always a mistake to install a new MacOS on an old Mac (even if not very old). If for some reason you want a new version, buy a new Mac. :~( Sorry... (It's even worse with a new iOS on an old iPhone.)
But, yeah, it was a bummer that you couldn't present.
Thanks for your suggestion Brian 
Unfortunately I didn't know. It is my first Mac.
Thanks Michael. I'm not an absolute fan of Chrome vs Safari (even if there are things that I like better in Chrome) but my problem with Chrome is that, as far as I understood from the bits of Jen's talk that I caught, Snap is going to be even more Chrome-centered? And, if I'm not wrong, Snap is supposed to run faster on Chrome?
But his Mac is new! 
And it really depends...some years are better than others, but the unfortunate solution may be to wipe it clean. Maybe this helps? https://www.makeuseof.com/tag/fix-mac-kernel-task-high-cpu-usage/
Also @s_federici you might see how Zoom performs in Firefox. Zoom really doesn't like Safari, but FF should work well and might be less taxing than chrome.
Not really! Snap! is going to support WebSerial, which works only on Chrome, but that doesn't mean it will become more Chrome-centered or run faster on Chrome. Hopefully, Firefox will eventually realize that serial devices pose less privacy issues than webcams or microphones and give in to implementing WebSerial too.
I exclusively use Firefox (like everybody should, unless they want the whole Web to be shaped by EvilCorp in 2 years time), and Snap! runs perfectly fine in it, as does the rest of the Internet save for WebSerial 
Good to know I knew that the Chrome JS VM was faster than Firefox's, I'm happy this is not the case anymore at least for Snap.
I hope so
I think things are getting pretty close! And I haven't played with it much, but Edge on macOS is getting pretty interesting. It's based on V8 (The Chrome VM) but with less...Chrome stuff...
Oh BTW @s_federici if you would like to record a version of your talk and send it me and Jadga, we'd be able to upload it to youtube and I can include it in an announcements/updates email after the conference.
But no pressure! just wanted to make the offer available.
Thanks a lot for the very kind offer. I hope to be able to prepare a recording when I'm back from vacation.