Re: A test for replay of regression tests

Hi,

On 2022-01-17 17:25:19 +1300, Thomas Munro wrote:
> I reordered the arguments, tested locally under the buildfarm client script,
> and pushed. I'll keep an eye on the build farm.

After the reloptions fix the tests seem much more likely to succeed than
before. Progress!

Unfortunately we don't quite seem there yet:

I saw a couple failures like:
https://api.cirrus-ci.com/v1/artifact/task/5394938773897216/regress_diffs/build/testrun/recovery/t/027_stream_regress/regression.diffs
(from https://cirrus-ci.com/task/5394938773897216?logs=check_world#L183 )

-- Should succeed
DROP TABLESPACE regress_tblspace_renamed;
+ERROR: tablespace "regress_tblspace_renamed" is not empty

I assume the reason we see this semi-regularly when the regression tests run
as part of 027_stream_regress, but not in the main regression test run, is
similar to the reloptions problem, namely that we run with a much smaller
shared buffers.

I assume what happens is that this just makes the known problem of bgwriter or
some other process keeping open a filehandle to an already deleted relation,
preventing the deletion to "fully" take effect, worse.

Greetings,

Andres Freund