On Tue, Mar 23, 2021 at 8:47 AM Drouvot, Bertrand <
bdrouvot@amazon.com> wrote:
>
> I have one remark regarding the conflicts:
>
> The logical slots are dropped if a conflict is detected.
>
> But, if the slot is not active before being dropped (say wal_level is changed to < logical on master and a logical slot is not active on the standby) then its corresponding pg_stat_database_conflicts.confl_logicalslot is not incremented (as it would be incremented "only" during the cancel of an "active" backend).
>
> I think, it should be incremented in all the cases (active or not), what do you think?
>
Good catch... IMHO it should be incremented as well!!!
> I updated the patch to handle this scenario (see the new pgstat_send_droplogicalslot() in v12-0003-Handle-logical-slot-conflicts-on-standby.patch).
>
Perfect.
> I also added more tests in
023_standby_logical_decoding_conflicts.pl to verify that pg_stat_database_conflicts.confl_logicalslot is updated as expected (see check_confl_logicalslot() in v12-0004-New-TAP-test-for-logical-decoding-on-standby.patch).
>
Perfect.
> Except this remark and the associated changes, then it looks good to me.
>
LGTM too... Reviewing new changes now to move it forward and make this patch set ready for commiter review.
Regards,
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