One thing I'd be interested in, which kind of belongs in this space:

In the last years, there were lots of performance reducing software patches for security flaws in CPUs, e.g. meltdown, specter and god knows what. Is there a way to disable those security fixes and increase performance, e.g. for servers that only ever run self written backend code and if so, is it common practice?

I feel like I wouldn't want those security fixes on that server I am running which only runs postgres, is only accessible to other servers via the postgres port and does nothing else.