As I promised on Twitter, I selected a couple of talks from the event that I liked very much (I almost feel guilty of selecting just a few of these, because there were so many great talks in the event).
For the Twitter addicts like me, I included the links to the speakers profiles so you can follow them.
Understanding CPU microarchitecture by Alex Blewitt.
The Revolving Door Performance Anti-Pattern by Kirk Pepperdine.
The Secrets of the Fastest Java Developers on Earth by Victor Rentea.
Project Loom: Revolution in concurrency or obscure implementation detail? by Tomasz Nurkiewicz.
Query your codebase using CodeQL by Benjamin Muskalla.
In addition to the talks above, I also recommend these talks below. These are talks that I already know the subject or have watched in the past, so I skipped watching them, but I know they are great talks. I think they might be very interesting too.
By the power of Java : Main of the Cloud-ivers !!! by Jonathan Vila.
Continuous Performance Regression Testing with JfrUnit by Gunnar Morling.
Benefits of MQTT for IoT Apps and Beyond by Mary Grygleski.
There are a lot more interesting talks for this conference. I recommend you to check the whole set of videos in their channel.