MariaDB [(none)]> select @@slave_parallel_threads,@@slave_parallel_mode;

+--------------------------+-----------------------+

| @@slave_parallel_threads | @@slave_parallel_mode |

+--------------------------+-----------------------+

|                        4 | optimistic            |

+--------------------------+-----------------------+

1 row in set (0.003 sec)

show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 116937038

                Relay_Log_File: ip-172-31-0-20-relay-bin.000004

                 Relay_Log_Pos: 116937334

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 116937038

               Relay_Log_Space: 116937696

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 0

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-11376

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 0

           SQL_Remaining_Delay: NULL

       Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates

              Slave_DDL_Groups: 38

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 4395

1 row in set (0.000 sec)

MariaDB [(none)]> stop slave;change master to master_delay=3600; start slave;

Query OK, 0 rows affected (1.244 sec)

Query OK, 0 rows affected (0.028 sec)

Query OK, 0 rows affected (0.006 sec)

MariaDB [(none)]> show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 259041585

                Relay_Log_File: ip-172-31-0-20-relay-bin.000002

                 Relay_Log_Pos: 552

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 256

               Relay_Log_Space: 81802918

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 0

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-11647

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 3600

           SQL_Remaining_Delay: 3421

       Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master executed event

              Slave_DDL_Groups: 38

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 4510

1 row in set (0.000 sec)

MariaDB [(none)]> show processlist;

+-----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

| Id  | User        | Host      | db   | Command      | Time | State                                                          | Info             | Progress |

+-----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

|  11 | root        | localhost | NULL | Query        |    0 | starting                                                       | show processlist |    0.000 |

|  95 | system user |           | NULL | Slave_IO     |    7 | Waiting for master to send event                               | NULL             |    0.000 |

|  97 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  98 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  99 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 100 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  96 | system user |           | NULL | Slave_SQL    |    7 | Waiting until MASTER_DELAY seconds after master executed event | NULL             |    0.000 |

+-----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

7 rows in set (0.000 sec)

MariaDB [(none)]> show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 386463738

                Relay_Log_File: ip-172-31-0-20-relay-bin.000002

                 Relay_Log_Pos: 552

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 256

               Relay_Log_Space: 209225071

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 0

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-11890

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 3600

           SQL_Remaining_Delay: 3412

       Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master executed event

              Slave_DDL_Groups: 38

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 4510

1 row in set (0.000 sec)

MariaDB [(none)]> \q

Bye

--Restart the MariaDB service 

[root@ip-172-31-0-20 mysql]# systemctl restart mariadb

MariaDB [(none)]> \s

--------------

mysql  Ver 15.1 Distrib 10.6.15-10-MariaDB, for Linux (x86_64) using readline 5.1

Connection id:		11

Current database:

Current user:		root@localhost

SSL:			Not in use

Current pager:		stdout

Using outfile:		''

Using delimiter:	;

Server:			MariaDB

Server version:		10.6.15-10-MariaDB-enterprise-log MariaDB Enterprise Server

Protocol version:	10

Connection:		Localhost via UNIX socket

Server characterset:	latin1

Db     characterset:	latin1

Client characterset:	utf8mb3

Conn.  characterset:	utf8mb3

UNIX socket:		/var/lib/mysql/mysql.sock

Uptime:			59 sec

Threads: 7  Questions: 6  Slow queries: 0  Opens: 16  Open tables: 10  Queries per second avg: 0.101

MariaDB [(none)]> show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 293650040

                Relay_Log_File: ip-172-31-0-20-relay-bin.000002

                 Relay_Log_Pos: 552

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 256

               Relay_Log_Space: 116411373

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 201

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-11712

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 3600

           SQL_Remaining_Delay: 3399

       Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master executed event

              Slave_DDL_Groups: 0

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 0

1 row in set (0.000 sec)

MariaDB [(none)]> show processlist;

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

| Id | User        | Host      | db   | Command      | Time | State                                                          | Info             | Progress |

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

|  5 | system user |           | NULL | Slave_IO     |    8 | Waiting for master to send event                               | NULL             |    0.000 |

|  7 | system user |           | NULL | Slave_worker |    8 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  8 | system user |           | NULL | Slave_worker |    8 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  9 | system user |           | NULL | Slave_worker |    8 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 10 | system user |           | NULL | Slave_worker |    8 | Waiting for work from SQL thread                               | NULL             |    0.000 |

|  6 | system user |           | NULL | Slave_SQL    |    5 | Waiting until MASTER_DELAY seconds after master executed event | NULL             |    0.000 |

| 11 | root        | localhost | NULL | Query        |    0 | starting                                                       | show processlist |    0.000 |

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

7 rows in set (0.000 sec)

MariaDB [(none)]> show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 975396633

                Relay_Log_File: ip-172-31-0-20-relay-bin.000002

                 Relay_Log_Pos: 552

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 256

               Relay_Log_Space: 798157966

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 606

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-13023

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 3600

           SQL_Remaining_Delay: 2994

       Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master executed event

              Slave_DDL_Groups: 0

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 0

1 row in set (0.000 sec)

MariaDB [(none)]> stop slave;

Query OK, 0 rows affected (0.003 sec)

MariaDB [(none)]> start slave;

Query OK, 0 rows affected (0.060 sec)

MariaDB [(none)]> show slave status\G

*************************** 1. row ***************************

                Slave_IO_State: Waiting for master to send event

                   Master_Host: 172.31.44.153

                   Master_User: repl_user

                   Master_Port: 3306

                 Connect_Retry: 60

               Master_Log_File: master.000012

           Read_Master_Log_Pos: 216567503

                Relay_Log_File: ip-172-31-0-20-relay-bin.000002

                 Relay_Log_Pos: 552

         Relay_Master_Log_File: master.000012

              Slave_IO_Running: Yes

             Slave_SQL_Running: Yes

               Replicate_Do_DB:

           Replicate_Ignore_DB:

            Replicate_Do_Table:

        Replicate_Ignore_Table:

       Replicate_Wild_Do_Table:

   Replicate_Wild_Ignore_Table:

                    Last_Errno: 0

                    Last_Error:

                  Skip_Counter: 0

           Exec_Master_Log_Pos: 256

               Relay_Log_Space: 39328836

               Until_Condition: None

                Until_Log_File:

                 Until_Log_Pos: 0

            Master_SSL_Allowed: No

            Master_SSL_CA_File:

            Master_SSL_CA_Path:

               Master_SSL_Cert:

             Master_SSL_Cipher:

                Master_SSL_Key:

         Seconds_Behind_Master: 0

 Master_SSL_Verify_Server_Cert: No

                 Last_IO_Errno: 0

                 Last_IO_Error:

                Last_SQL_Errno: 0

                Last_SQL_Error:

   Replicate_Ignore_Server_Ids:

              Master_Server_Id: 1

                Master_SSL_Crl:

            Master_SSL_Crlpath:

                    Using_Gtid: Slave_Pos

                   Gtid_IO_Pos: 0-1-11565

       Replicate_Do_Domain_Ids:

   Replicate_Ignore_Domain_Ids:

                 Parallel_Mode: optimistic

                     SQL_Delay: 3600

           SQL_Remaining_Delay: 2984

       Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master executed event

              Slave_DDL_Groups: 0

Slave_Non_Transactional_Groups: 0

    Slave_Transactional_Groups: 0

1 row in set (0.000 sec)

MariaDB [(none)]> show processlist;

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

| Id | User        | Host      | db   | Command      | Time | State                                                          | Info             | Progress |

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

| 11 | root        | localhost | NULL | Query        |    0 | starting                                                       | show processlist |    0.000 |

| 12 | system user |           | NULL | Slave_IO     |    7 | Waiting for master to send event                               | NULL             |    0.000 |

| 14 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 15 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 16 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 17 | system user |           | NULL | Slave_worker |    7 | Waiting for work from SQL thread                               | NULL             |    0.000 |

| 13 | system user |           | NULL | Slave_SQL    |    5 | Waiting until MASTER_DELAY seconds after master executed event | NULL             |    0.000 |

+----+-------------+-----------+------+--------------+------+----------------------------------------------------------------+------------------+----------+

7 rows in set (0.000 sec)