Upgrade is looking quite uneventful, which is great. Performance is even and remains incredibly similar.
Memory and CPU look remarkably similar.
My only concern (and something I would like to get to the bottom of) it appears we get “runaway” threads for a few seconds regularly on the web workers.
So somehow, some requests are causing a huge number of threads to be spawned and then go away.
Will continue to investigate this, we need to get backtraces when the number is high, so we can find the culprit.
Given everything else is looking really good I will not be reverting the upgrade.