Re: basebackup: do not verify checksums on pages written before enabling checksums

Hi,

On Fri, Aug 14, 2026 at 09:57:32PM +0200, Daniel Gustafsson wrote:
> > On 14 Aug 2026, at 21:36, Zsolt Parragi <zsolt(dot)parragi(at)percona(dot)com> wrote:

Thanks for the report and the patch!

> > I am not 100% happy with the shape of the patch, but I couldn't come
> > up with a better solution even after staring at it for a long time,
> > and I think it is at least correct and good enough. But maybe somebody
> > has a better idea for solving this problem.
>
> Thanks! I wasn't able to come up with a mor elegant solution either when
> staring at it but I'll take another look at it together with the other fixes
> staged.

I had a look and I wonder if the boolean could miss an on->off->on series of
changes. checksums_on_at_start would remain true in that case. Once checksums
are enabled again, we'd resume verification even though the final checkpoint may
still be running.

Maybe tracking a checksum transition generation/LSN would make this easier to
reason about? Or am I missing something preventing this case?

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com