server closed the connection message in the log file of standby while performing logical replication synchronization

Hi,

I am getting server closed the connection message in the log file of
standby after 'logical replication synchronization worker finished
processing' LOG message

2017-05-24 08:58:04.451 BST [28496] LOG: logical replication sync for
subscription s_5434, table t1039 started
2017-05-24 08:58:05.447 BST [28388] LOG: starting logical replication
worker for subscription "s_5434"
2017-05-24 08:58:05.453 BST [28498] LOG: logical replication sync for
subscription s_5434, table t104 started
2017-05-24 08:58:06.449 BST [28388] LOG: starting logical replication
worker for subscription "s_5434"
2017-05-24 08:58:06.455 BST [28500] LOG: logical replication sync for
subscription s_5434, table t1040 started
2017-05-24 08:58:07.451 BST [28388] LOG: starting logical replication
worker for subscription "s_5434"
2017-05-24 08:58:07.458 BST [28502] LOG: logical replication sync for
subscription s_5434, table t1041 started
2017-05-24 08:58:08.453 BST [28388] LOG: starting logical replication
worker for subscription "s_5434"
2017-05-24 08:58:08.461 BST [28504] LOG: logical replication sync for
subscription s_5434, table t1042 started
2017-05-24 08:58:23.540 BST [28463] LOG: logical replication
synchronization worker finished processing
2017-05-24 08:58:23.550 BST [28461] LOG: logical replication
synchronization worker finished processing
2017-05-24 08:58:08.453 BST [28388] LOG: starting logical replication
worker for subscription "s_5434"
2017-05-24 08:58:08.461 BST [28504] LOG: logical replication sync for
subscription s_5434, table t1042 started
2017-05-24 08:58:23.540 BST [28463] LOG: logical replication
synchronization worker finished processing
2017-05-24 08:58:23.550 BST [28461] LOG: logical replication
synchronization worker finished processing
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
2017-05-24 08:59:23.622 BST [28465] ERROR: error reading result of
streaming command: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
2017-05-24 08:59:23.627 BST [28340] LOG: worker process: logical
replication worker for subscription 31385 sync 19463 (PID 28465) exited
with exit code 1
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
2017-05-24 08:59:33.624 BST [28467] ERROR: error reading result of
streaming command: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.

Steps to reproduce -

X Cluster -
Modify/add this below parameters in postgresql.conf file
wal_level=logical
logging_collector=on
max_replication_slots = 100
max_worker_processes = 50
max_logical_replication_workers = 35
max_sync_workers_per_subscription = 25
max_wal_senders=50
log_min_duration_statement = 0
port=5432

Start the server

connect to psql
create 5000 tables
create publication -> create publication pub for all tables;

Y Cluster-

Modify/add this below parameters in postgresql.conf file

wal_level=logical
logging_collector=on
max_replication_slots = 100
max_worker_processes = 50
max_logical_replication_workers = 35
max_sync_workers_per_subscription = 25
max_wal_senders=50
log_min_duration_statement = 0
port=5433

Start the server

connect to psql
create 5000 tables
create subscription ->create subscription suv connection
'dbname=postgres port=5432 user=centos host=localhost' publication pub;

check the log file on standby ( in 5-10 minutes , server closed ...
message should come)

attaching both log files ( master and standby).

reproducing this issue is not consistent. Out of 5 times, i am able to
reproduce it 2 times only.

--
regards,tushar
EnterpriseDB https://www.enterprisedb.com/
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