Your app is slow. It does not spark joy. This post will use memory allocation profiling tools to discover performance hotspots, even when they're coming from inside a library. We will use this technique with a real-world application to identify a piece of optimizable code in Active Record that ultimately leads to a patch with a substantial impact on page speed.
In addition to the talk, I've gone back and written a full technical recap of each section to revisit it any time you want without going through the video.
I make heavy use of theatrics here, including a Japanese voiceover artist, animoji, and some edited clips of Marie Kondo's Netflix TV show. This recording was done...