The primary tables used for this purpose are:
- replication_group_members
- replication_group_member_stats
- replication_group_members Table
This table displays network and status information for replication group members. The network addresses shown are the ones used to connect clients to the group.
mysql> SELECT * FROM performance_schema.replication_group_members;
+---------------------------+--------------------------------------+----------------+-------------+--------------+-------------+----------------+----------------------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | MEMBER_ROLE | MEMBER_VERSION | MEMBER_COMMUNICATION_STACK |
+---------------------------+--------------------------------------+----------------+-------------+--------------+-------------+----------------+----------------------------+
| group_replication_applier | 13fc049e-c133-11ee-a377-000c29df1f85 | 192.168.131.20 | 3306 | ONLINE | SECONDARY | 8.0.27 | XCom |
| group_replication_applier | 248563ac-c133-11ee-a387-000c29551477 | 192.168.131.30 | 3306 | ONLINE | SECONDARY | 8.0.27 | XCom |
| group_replication_applier | f40395ea-c132-11ee-9249-000c29c00092 | 192.168.131.10 | 3306 | ONLINE | PRIMARY | 8.0.27 | XCom |
+---------------------------+--------------------------------------+----------------+-------------+--------------+-------------+----------------+----------------------------+
3 rows in set (0.00 sec)
Field Descriptions:
| Field | Description |
|---|---|
| CHANNEL_NAME | Group replication channel name |
| MEMBER_ID | Server UUID for the member. Unique for each member in the group |
| MEMBER_HOST | Network address (hostname or IP) of the member. This is the address clients connect to |
| MEMBER_PORT | Port the server is listening on |
| MEMBER_STATE | Current status of the member, which can be: - ON LINE: Member is fully functional - RECOVERING: Server has joined the group and is retrieving data - OFFLINE: Group replication plugin installed but not started - ERROR: Member encountered errors during transaction application - UNREACHABLE: Member suspected to be unreachable due to timeout |
| MEMBER_ROLE | Role of the member in the group (PRIMARY or SECONDARY) |
| MEMBER_VERSION | MySQL version of the member |
| MEMBER_COMMUNICATION_STACK | Communication stack used for the group (XCom or MySQL) |
- replication_group_member_stats Table
This table provides group-level information related to the certification process, along with statistics about transactions received and initiated by each member of the replication group.
mysql> SELECT * FROM performance_schema.replication_group_member_stats\G
*************************** 1. row ***************************
CHANNEL_NAME: group_replication_applier
VIEW_ID: 17082578864394446:3
MEMBER_ID: 13fc049e-c133-11ee-a377-000c29df1f85
COUNT_TRANSACTIONS_IN_QUEUE: 0
COUNT_TRANSACTIONS_CHECKED: 0
COUNT_CONFLICTS_DETECTED: 0
COUNT_TRANSACTIONS_ROWS_VALIDATING: 0
TRANSACTIONS_COMMITTED_ALL_MEMBERS: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-24
LAST_CONFLICT_FREE_TRANSACTION:
COUNT_TRANSACTIONS_REMOTE_IN_APPLIER_QUEUE: 1
COUNT_TRANSACTIONS_REMOTE_APPLIED: 1
COUNT_TRANSACTIONS_LOCAL_PROPOSED: 0
COUNT_TRANSACTIONS_LOCAL_ROLLBACK: 0
*************************** 2. row ***************************
CHANNEL_NAME: group_replication_applier
VIEW_ID: 17082578864394446:3
MEMBER_ID: 248563ac-c133-11ee-a387-000c29551477
COUNT_TRANSACTIONS_IN_QUEUE: 0
COUNT_TRANSACTIONS_CHECKED: 0
COUNT_CONFLICTS_DETECTED: 0
COUNT_TRANSACTIONS_ROWS_VALIDATING: 0
TRANSACTIONS_COMMITTED_ALL_MEMBERS: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-24
LAST_CONFLICT_FREE_TRANSACTION:
COUNT_TRANSACTIONS_REMOTE_IN_APPLIER_QUEUE: 1
COUNT_TRANSACTIONS_REMOTE_APPLIED: 0
COUNT_TRANSACTIONS_LOCAL_PROPOSED: 0
COUNT_TRANSACTIONS_LOCAL_ROLLBACK: 0
*************************** 3. row ***************************
CHANNEL_NAME: group_replication_applier
VIEW_ID: 17082578864394446:3
MEMBER_ID: f40395ea-c132-11ee-9249-000c29c00092
COUNT_TRANSACTIONS_IN_QUEUE: 0
COUNT_TRANSACTIONS_CHECKED: 0
COUNT_CONFLICTS_DETECTED: 0
COUNT_TRANSACTIONS_ROWS_VALIDATING: 0
TRANSACTIONS_COMMITTED_ALL_MEMBERS: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-24
LAST_CONFLICT_FREE_TRANSACTION:
COUNT_TRANSACTIONS_REMOTE_IN_APPLIER_QUEUE: 0
COUNT_TRANSACTIONS_REMOTE_APPLIED: 3
COUNT_TRANSACTIONS_LOCAL_PROPOSED: 0
COUNT_TRANSACTIONS_LOCAL_ROLLBACK: 0
3 rows in set (0.01 sec)
Field Descriptions:
| Field | Description |
|---|---|
| CHANNEL_NAME | Channel name |
| VIEW_ID | Group view ID |
| MEMBER_ID | Member UUID |
| COUNT_TRANSACTIONS_IN_QUEUE | Number of transactions in queue waiting for conflict detection |
| COUNT_TRANSACTIONS_CHECKED | Number of transactions that have been checked for conflicts |
| COUNT_CONFLICTS_DETECTED | Number of transactions that failed conflict detection |
| COUNT_TRANSACTIONS_ROWS_VALIDATING | Current number of rows being validated for conflicts |
| TRANSACTIONS_COMMITTED_ALL_MEMBERS | Transactions successfully committed on all group members, shown as GTID set (updated every 60 seconds) |
| LAST_CONFLICT_FREE_TRANSACTION | GTID of the last transaction checked without conflicts |
| COUNT_TRANSACTIONS_REMOTE_IN_APPLIER_QUEUE | Number of transactions received from the replication group waiting to be applied |
| COUNT_TRANSACTIONS_REMOTE_APPLIED | Number of transactions received from the replication group that have been applied |
| COUNT_TRANSACTIONS_LOCAL_PROPOSED | Number of transactions initiated by this member and sent to the group |
| COUNT_TRANSACTIONS_LOCAL_ROLLBACK | Number of transactions initiated by this member that were rolled back by the group |