Re: [PoC] pg_upgrade: allow to upgrade publisher node

On Wed, Oct 18, 2023 at 7:31 AM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
>
> ======
> src/bin/pg_upgrade/check.c
>
> 0.
> +check_old_cluster_for_valid_slots(bool live_check)
> +{
> + char output_path[MAXPGPATH];
> + FILE *script = NULL;
> +
> + prep_status("Checking for valid logical replication slots");
> +
> + snprintf(output_path, sizeof(output_path), "%s/%s",
> + log_opts.basedir,
> + "invalid_logical_relication_slots.txt");
>
> 0a
> typo /invalid_logical_relication_slots/invalid_logical_replication_slots/
>
> ~
>
> 0b.
> Since the non-upgradable slots are not strictly "invalid", is this an
> appropriate filename for the bad ones?
>
> But I don't have very good alternatives. Maybe:
> - non_upgradable_logical_replication_slots.txt
> - problem_logical_replication_slots.txt
>

I prefer the current naming. I think 'invalid' here indicates both
types of slots that are invalidated by the checkpointer and those that
have pending WAL to be consumed.

> ======
> src/bin/pg_upgrade/t/003_upgrade_logical_replication_slots.pl
>
> 1.
> +# ------------------------------
> +# TEST: Confirm pg_upgrade fails when wrong GUC is set on new cluster
> +#
> +# There are two requirements for GUCs - wal_level and max_replication_slots,
> +# but only max_replication_slots will be tested here. This is because to
> +# reduce the execution time of the test.
>
>
> SUGGESTION
> # TEST: Confirm pg_upgrade fails when the new cluster has wrong GUC values.
> #
> # Two GUCs are required - 'wal_level' and 'max_replication_slots' - but to
> # reduce the test execution time, only 'max_replication_slots' is tested here.
>

I think we don't need the second part of the comment: "Two GUCs ...".
Ideally, we should test each parameter's invalid value but that could
be costly, so I think it is okay to test a few of them.

--
With Regards,
Amit Kapila.