BUG #17870: Analyze on remote postgresql_fdw table never finish - Mailing list pgsql-bugs

The following bug has been logged on the website:

Bug reference:      17870
Logged by:          Maxim Boguk
Email address:      maxim.boguk@gmail.com
PostgreSQL version: 13.9
Operating system:   Linux
Description:

Hi,

I found strange situation when I try to populate local statistic from remote
postgesql_fdw table:
analyze verbose cold_replica_fdw.interview_review_info_archive;
- never ends,

Local and remote DB in the same datacenter with more total bandwidth 20Gbps
and latency under 0.1ms (both tested/verified), so no network issues.

What I see on local side with set client_min_messages to debug5;:
hh_data=# analyze verbose cold_replica_fdw.interview_review_info_archive;
DEBUG:  discarding connection 0x563656981900
DEBUG:  sinval catchup complete, cleaning queue
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state:
INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  CommitTransaction(1) name: unnamed; blockState: STARTED; state:
INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  StartTransaction(1) name: unnamed; blockState: DEFAULT; state:
INPROGRESS, xid/subid/cid: 0/1/0
DEBUG:  new postgres_fdw connection 0x56365698fc40 for server "cold_replica"
(user mapping oid 263996607, userid 10)
DEBUG:  starting remote transaction on connection 0x56365698fc40
INFO:  analyzing "cold_replica_fdw.interview_review_info_archive"
and  stays there for hours...

What I see on the remove database with log_min_duration_statement set to 0
to FDW user:
2023-03-27 10:11:24.763 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.086 ms  statement: SET
application_name='postgres_fdw';
2023-03-27 10:11:24.763 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.029 ms  statement: SET
search_path = pg_catalog
2023-03-27 10:11:24.764 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.166 ms  statement: SET timezone =
'UTC'
2023-03-27 10:11:24.764 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.023 ms  statement: SET datestyle
= ISO
2023-03-27 10:11:24.765 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.032 ms  statement: SET
intervalstyle = postgres
2023-03-27 10:11:24.765 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/0 txid:0] [SET] LOG:  duration: 0.032 ms  statement: SET
extra_float_digits = 3
2023-03-27 10:11:24.766 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/356802672 txid:0] [START TRANSACTION] LOG:  duration: 0.021 ms
statement: START TRANSACTION ISOLATION LEVEL REPEATABLE READ
2023-03-27 10:11:24.767 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/356802672 txid:0] [SELECT] LOG:  duration: 0.446 ms  statement:
SELECT
pg_catalog.pg_relation_size('public.interview_review_info_archive'::pg_catalog.regclass)
/ 8192
2023-03-27 10:11:24.861 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/356802672 txid:0] [DECLARE CURSOR] LOG:  duration: 92.942 ms
statement: DECLARE c1 CURSOR FOR SELECT topic_id, review_id,
move_to_invitation_state_time, no_interview_reply_time,
review_suggestion_chat_message_creation_time FROM
public.interview_review_info_archive
2023-03-27 10:11:28.268 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/356802672 txid:0] [FETCH] LOG:  duration: 3406.462 ms  statement:
FETCH 100 FROM c1
2023-03-27 10:11:28.269 UTC 636130
negotiation_chat_archive_ro.fdw@negotiation_chat_archive from [local]
[vxid:39/356802672 txid:0] [FETCH] LOG:  duration: 0.094 ms  statement:
FETCH 100 FROM c1

and then continue fetch forever, on the last attempt it fetched from cursor
over 5M times before I canceled analyze statement.

public.interview_review_info_archive - huge native partitioned by range
table with 100 partitions and 2TB+ size.

Is it expected that the analyze of foreign table will fetch whole table to
local size (quite a task for 2TB table)?

PS: I don't want enable a remote estimates because it adds huge planning
overhead (with remote_estimate 'true'):
 Foreign Scan on cold_replica_fdw.interview_review_info_archive
(cost=14.10..14.14 rows=1 width=40) (actual time=3.966..4.681 rows=1
loops=1)
   Output: topic_id, review_id, move_to_invitation_state_time,
no_interview_reply_time, review_suggestion_chat_message_creation_time
   Remote SQL: SELECT topic_id, review_id, move_to_invitation_state_time,
no_interview_reply_time, review_suggestion_chat_message_creation_time FROM
public.interview_review_info_archive ORDER BY topic_id ASC NULLS LAST LIMIT
1::bigint
 Planning Time: 13.646 ms
 Execution Time: 5.347 ms