Nobody sensible runs the latest kernel; nobody running PG in production should be afraid of setting a non-default at either boot time or as a sysctl. So this will, most likely, be another step in building a PG database server (turn off pre-emption if your kernel is 7.0 or later and PG is pre-whatever-version).

At worst it might become a permanent part of building a PG server and a FAQ... but if it affects one thing this badly, it will affect others.

Its worth reading this follow-up LKML post by Andres Freund (who works on Postgres): https://lore.kernel.org/lkml/yr3inlzesdb45n6i6lpbimwr7b25kqk...

Once upon a time, Linus would shout and yell about how the kernel should never "break" userspace.

Now, the kernel engineer who introduced the brand new mechanism (introduced in Linux 7.0) for handling pre-emption says the "fix" is for Postgres to start using this new mechanism (I think the sister comment below links to what one of the Postgres engineers thinks of that, and I'm inclined mostly to agree).