[pgpool-general: 8214] Pgpool reporting inconsistent statuses

[Felix Rubio]

Hi everybody,

I have managed to set up, from scratch, a postgresql 14 + pgpool 4.3.2 
cluster, with streaming replication. I have also a simple test that 
creates a database, a table on it, and adds some records, to then check 
on all the members of the cluster if replication has been successful.

If I point my test to the primary node of the streaming replication 
cluster, my test succeeds and all is OK.

When I set up everything through pgpool, all seems to work:

  node_id |  hostname  | port | status | pg_status | lb_weight |  role   
| pg_role | select_cnt | load_balance_node | replication_delay | 
replication_state | replication_sync_state | last_status_change
---------+------------+------+--------+-----------+-----------+---------+---------+------------+-------------------+-------------------+-------------------+------------------------+---------------------
  0       | pgsql-0000 | 5433 | up     | up        | 0.333333  | primary 
| primary | 0          | false             | 0                 |         
           |                        | 2022-06-14 11:28:11
  1       | pgsql-0001 | 5433 | up     | up        | 0.333333  | standby 
| standby | 0          | false             | 0                 | 
streaming         | async                  | 2022-06-14 11:28:11
  2       | pgsql-0002 | 5433 | up     | up        | 0.333333  | standby 
| standby | 0          | true              | 0                 | 
streaming         | async                  | 2022-06-14 11:28:11


If now run my test, this is what I get back:
"DETAIL:  kind does not match between main(53) slot[1] (45)"

I have found an article claiming this is a problem caused by the number 
of connections. To this end, I have max_connections=40 in postgresql, 
and num_init_children=7 and max_pool=5 in pgpool.conf. As 5*7 < 40, I 
should ok on the side. Does anybody has a clue on what might be going 
on, here?

Regards!

-- 
Felix Rubio
"Don't believe what you're told. Double check."