RE: Synchronizing slots from primary to standby

On Friday, February 9, 2024 6:45 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> 
> On Fri, Feb 9, 2024 at 10:00 AM Zhijie Hou (Fujitsu) <houzj.fnst@fujitsu.com>
> wrote:
> >
> 
> Few comments on 0001
> ===================
> 1. Shouldn't pg_sync_replication_slots() check whether the user has replication
> privilege?

Yes, added.

> 
> 2. The function declarations in slotsync.h don't seem to be in the same order as
> they are defined in slotsync.c. For example, see ValidateSlotSyncParams(). The
> same is true for new functions exposed via walreceiver.h and walsender.h. Please
> check the patch for other such inconsistencies.

I reordered the function declarations.

> 
> 3.
> +# Wait for the standby to finish sync
> +$standby1->wait_for_log(
> + qr/LOG: ( [A-Z0-9]+:)? newly created slot \"lsub1_slot\" is sync-ready
> +now/,  $offset);
> +
> +$standby1->wait_for_log(
> + qr/LOG: ( [A-Z0-9]+:)? newly created slot \"lsub2_slot\" is sync-ready
> +now/,  $offset);
> +
> +# Confirm that the logical failover slots are created on the standby
> +and are # flagged as 'synced'
> +is($standby1->safe_psql('postgres',
> + q{SELECT count(*) = 2 FROM pg_replication_slots WHERE slot_name IN
> ('lsub1_slot', 'lsub2_slot') AND synced;}),
> + "t",
> + 'logical slots have synced as true on standby');
> 
> Isn't the last test that queried pg_replication_slots sufficient? I think
> wait_for_log() would be required for slotsync worker or am I missing something?

I think it's not needed in 0001, so removed.

> Apart from the above, I have modified a few comments in the attached.

Thanks, it looks good to me, so applied.

Attach the V83 patch which addressed Peter[1][2], Amit and Sawada-san's[3]
comments. Only 0001 is sent in this version, we will send other patches after
rebasing.

[1] https://www.postgresql.org/message-id/CAHut%2BPvW8s6AYD2UD0xadM%2B3VqBkXP2LjD30LEGRkHUa-Szm%2BQ%40mail.gmail.com
[2] https://www.postgresql.org/message-id/CAHut%2BPv88vp9mNxX37c_Bc5FDBsTS%2BdhV02Vgip9Wqwh7GBYSg%40mail.gmail.com
[3] https://www.postgresql.org/message-id/CAD21AoDvyLu%3D2-mqfGn_T_3jUamR34w%2BsxKvYnVzKqTCpyq_FQ%40mail.gmail.com

Best Regards,
Hou zj