[MDEV-17368] RESET MASTER doesn't completely reset gtid_current_pos - Jira

Details

Type: Bug
Status: Closed (View Workflow)
Priority: Major
Resolution: Not a Bug
Affects Version/s: 10.1.34
Fix Version/s: N/A
Component/s: Replication
Labels:
- binlog
- gtid

Description

RESET MASTER mostly resets gtid_current_pos, but it doesn't seem to reset it entirely:

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 1-1-29,3-1-99971          | 1-1-29,3-1-99971         |

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

1 row in set (0.00 sec)

MariaDB [(none)]> RESET MASTER;

Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    |                          |

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

1 row in set (0.00 sec)

I don't know where this leftover GTID is from and why it wasn't deleted. It obviously came from another server, since this specific server does not have server_id=2:

MariaDB [(none)]> SELECT @@global.server_id;

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

| @@global.server_id |

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

|                  1 |

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

1 row in set (0.00 sec)

This server is not currently a slave and it is not currently in a Galera Cluster, so it's not like it could have replicated this transaction after I executed RESET MASTER:

MariaDB [(none)]> SHOW SLAVE STATUS\G

Empty set (0.00 sec)

MariaDB [(none)]> SHOW GLOBAL STATUS LIKE 'wsrep%';

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

| Variable_name            | Value                |

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

| wsrep_cluster_conf_id    | 18446744073709551615 |

| wsrep_cluster_size       | 0                    |

| wsrep_cluster_state_uuid |                      |

| wsrep_cluster_status     | Disconnected         |

| wsrep_connected          | OFF                  |

| wsrep_local_bf_aborts    | 0                    |

| wsrep_local_index        | 18446744073709551615 |

| wsrep_provider_name      |                      |

| wsrep_provider_vendor    |                      |

| wsrep_provider_version   |                      |

| wsrep_ready              | OFF                  |

| wsrep_thread_count       | 0                    |

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

12 rows in set (0.00 sec)

It seems as though there is a bug in RESET MASTER that prevents it from completely resetting gtid_current_pos.

Attachments

Issue Links

relates to

MDEV-17369 Document how to reset gtid_current_pos

Closed

MDEV-17370 Create method to purge a specific domain from gtid_binlog_pos

Closed

MDEV-17853 Document that gtid_binlog_pos can lag behind gtid_current_pos after RESET MASTER

Closed

MDEV-17867 Make RESET MASTER throw GTID-related warning if gtid_slave_pos is set

Open

MDEV-17156 Local transactions on a Slave don't update GTID's gtid_current_pos after RESET MASTER on Slave (master_use_gtid value is not relevant)

Closed

Activity

Ascending order - Click to sort in descending order

Geoff Montee (Inactive) added a comment - 2018-10-04 23:03

What's also interesting is that no matter how many times I execute RESET MASTER, this GTID doesn't go away:

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-1-55                    | 3-1-55                   |

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

1 row in set (0.00 sec)

MariaDB [(none)]> RESET MASTER;

Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    |                          |

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

1 row in set (0.00 sec)

MariaDB [(none)]> RESET MASTER;

Query OK, 0 rows affected (0.01 sec)

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    |                          |

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

1 row in set (0.00 sec)

And it even seems possible to make gtid_current_pos and gtid_binlog_pos get out of sync:

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    |                          |

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

1 row in set (0.00 sec)

MariaDB [(none)]> USE db1;

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

MariaDB [db1]> INSERT INTO test_table VALUES (1000000, 100);

Query OK, 1 row affected (0.01 sec)

MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    | 3-1-1                    |

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

1 row in set (0.00 sec)

MariaDB [db1]> INSERT INTO test_table VALUES (1000001, 100);

Query OK, 1 row affected (0.01 sec)

MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    | 3-1-2                    |

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

1 row in set (0.00 sec)

MariaDB [db1]> RESET MASTER;

Query OK, 0 rows affected (0.00 sec)

MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

| 3-2-54                    |                          |

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

1 row in set (0.00 sec)

Geoff Montee (Inactive) added a comment - 2018-10-04 23:03 What's also interesting is that no matter how many times I execute RESET MASTER, this GTID doesn't go away: MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-1-55 | 3-1-55 | +---------------------------+--------------------------+ 1 row in set (0.00 sec) MariaDB [(none)]> RESET MASTER; Query OK, 0 rows affected (0.00 sec) MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | | +---------------------------+--------------------------+ 1 row in set (0.00 sec) MariaDB [(none)]> RESET MASTER; Query OK, 0 rows affected (0.01 sec) MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | | +---------------------------+--------------------------+ 1 row in set (0.00 sec) And it even seems possible to make gtid_current_pos and gtid_binlog_pos get out of sync: MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | | +---------------------------+--------------------------+ 1 row in set (0.00 sec) MariaDB [(none)]> USE db1; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed MariaDB [db1]> INSERT INTO test_table VALUES (1000000, 100); Query OK, 1 row affected (0.01 sec) MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | 3-1-1 | +---------------------------+--------------------------+ 1 row in set (0.00 sec) MariaDB [db1]> INSERT INTO test_table VALUES (1000001, 100); Query OK, 1 row affected (0.01 sec) MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | 3-1-2 | +---------------------------+--------------------------+ 1 row in set (0.00 sec) MariaDB [db1]> RESET MASTER; Query OK, 0 rows affected (0.00 sec) MariaDB [db1]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | 3-2-54 | | +---------------------------+--------------------------+ 1 row in set (0.00 sec)

Geoff Montee (Inactive) added a comment - 2018-10-04 23:11 - edited

I figured it out. mysql.gtid_slave_pos had some GTIDs leftover from when the server was a slave. I fixed it with:

MariaDB [(none)]> SET GLOBAL gtid_slave_pos='';

Query OK, 0 rows affected (0.01 sec)

MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos;

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

| @@global.gtid_current_pos | @@global.gtid_binlog_pos |

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

|                           |                          |

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

1 row in set (0.00 sec)

Geoff Montee (Inactive) added a comment - 2018-10-04 23:11 - edited I figured it out. mysql.gtid_slave_pos had some GTIDs leftover from when the server was a slave. I fixed it with: MariaDB [(none)]> SET GLOBAL gtid_slave_pos=''; Query OK, 0 rows affected (0.01 sec) MariaDB [(none)]> SELECT @@global.gtid_current_pos, @@global.gtid_binlog_pos; +---------------------------+--------------------------+ | @@global.gtid_current_pos | @@global.gtid_binlog_pos | +---------------------------+--------------------------+ | | | +---------------------------+--------------------------+ 1 row in set (0.00 sec)

MariaDB Server

RESET MASTER doesn't completely reset gtid_current_pos

Details

Description

Attachments

Issue Links

Activity

People

Dates

Git Integration