Re: Changing the state of data checksums in a running cluster

On Fri, Nov 21, 2025 at 01:17:09PM +0100, Tomas Vondra wrote:
> True. Hence the stress testing I've been doing - and indeed, that made
> us discover the various issues reported in this thread.
>
> Still, isn't that similar to error paths in various other patches? Those
> also tend to be rarely exercised in practice. I think the right way to
> address that is more testing. Of course, there's a difference between
> "regular bugs" and "design problems". Some of the issues are more about
> the design/architecture not considering something important.
>
> I don't know if / when this will be ready for commit. Maybe never, who
> knows. I prefer going step by step. We know about a couple issues, we
> need to figure out what to do about those. Then we can reconsider.
>
> FWIW I'm not sure the number of people currently enabling checksums on
> production databases is a good metric of how important the patch is.
> Maybe more people would like to do that, but can't accept the downtime.

I think it is a worth-while feature. We would have had it years ago
except that people asked for re-start-ability after a crash, and since
we don't have restart logic at the relation level, the patch got too
complex and was abandoned.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

Do not let urgent matters crowd out time for investment in the future.