Re: relfrozenxid may disagree with row XIDs after 1ccc1e05ae

On Thu, May 9, 2024 at 5:56 PM Melanie Plageman
<melanieplageman(at)gmail(dot)com> wrote:
>
> I can repro the hang on 14 and 15 with the following:

-- snip --

I finally managed to write a TAP test which does the same thing as my
repro. The attached patch contains a test that is meant purely for
demonstration and reproduction by others -- not as a suggestion to add
to the recovery test suite on an ongoing basis.

I also attached the fix (targeting REL_15_STABLE) so that you can try
the repro TAP test with and without the fix.

The test is a bit fragile, so I won't be surprised if it doesn't work
for everyone.

Thank you so much to Andres, Thomas, and Daniel, all of whom helped me
debug various issues I was having with trying to make background_psql
work reliably for this test on 15. This was truly painful, but I never
would have gotten through it without my IPC::Run support group.

I'll probably add more robust comments to the test next week in
preparation for writing a detailed commit message for the fix
explaining the scenario.

- Melanie