Re: Corner-case bug in pg_rewind

On 01/12/2020 16:52, Pavel Borisov wrote:
> Status update for a commitfest entry.
>
> The patch is Waiting on Author for some time. As this is a bug fix,
> I am
> moving it to the next CF.
> Ian, are you planning to continue working on it?
>
> As a reviewer, I consider the patch useful and good overall. The
> comments I left were purely cosmetic. It's a pity to me that this bugfix
> delayed for such a small reason and outdated, therefore. It would be
> nice to complete this fix on the next CF.

Yeah, we really should fix this..

On 16/11/2020 04:49, Ian Lawrence Barwick wrote:
>> Also, I think Heikki's notion could be fulfilled.
>
> I spent a bit of time looking at that suggestion but couldn't actually
> verify it was an issue which needed fixing.

Attached are two patches. The first patch is your original patch,
unmodified (except for a cosmetic rename of the test file). The second
patch builds on that, demonstrating and fixing the issue I mentioned. It
took me a while to create a repro for it, it's easily masked by
incidental full-page writes or because rows created by XIDs that are not
marked as committed on the other timeline are invisible, but succeeded
at last.

- Heikki