-- CONFLICT DETECTED -- between "DESCRIBE table_name" and "FLUSH PRIVILEGES"

General Questions
1

Transactions locks should be only on DDL commands.
GRANT and “FLUSH PRIVILEGES” are DCL coomands. Theys should’nt cause cluster conflict?
Our app very often uses “DESCRIBE table_name”, and we sometimes granting permissions. On granting we get an error.log. How to avoid this?

2023-03-10T10:58:16.625799-00:00 14 [Note] [MY-000000] [WSREP] --------- CONFLICT DETECTED --------
2023-03-10T10:58:16.625821-00:00 14 [Note] [MY-000000] [WSREP] cluster conflict due to high priority abort for threads:

2023-03-10T10:58:16.625843-00:00 14 [Note] [MY-000000] [WSREP] Winning thread:
   THD: 14, mode: toi, state: exec, conflict: committed, seqno: 1104217939
   SQL: FLUSH PRIVILEGES

2023-03-10T10:58:16.625865-00:00 14 [Note] [MY-000000] [WSREP] Victim thread:
   THD: 6628131, mode: local, state: exec, conflict: executing, seqno: -1
   SQL: DESCRIBE `table_1`

2023-03-10T10:58:24.041941-00:00 17 [Note] [MY-000000] [WSREP] --------- CONFLICT DETECTED --------
2023-03-10T10:58:24.042019-00:00 17 [Note] [MY-000000] [WSREP] cluster conflict due to high priority abort for threads:

2023-03-10T10:58:24.042050-00:00 17 [Note] [MY-000000] [WSREP] Winning thread:
   THD: 17, mode: toi, state: exec, conflict: committed, seqno: 1104218951
   SQL: GRANT ALTER, ALTER ROUTINE, CREATE, CREATE ROUTINE, CREATE TEMPORARY TABLES, CREATE VIEW, DELETE, DROP, EVENT, INDEX, INSERT, REFERENCES, TRIGGER, UPDATE, LOCK TABLES  ON `wrg_%`.* TO 'devuser35'@'%'

2023-03-10T10:58:24.042077-00:00 17 [Note] [MY-000000] [WSREP] Victim thread:
   THD: 6628673, mode: local, state: exec, conflict: executing, seqno: -1
   SQL: DESCRIBE `table_2`
2

Hello @Modestas_Mockus,
While GRANT and FLUSH PRIVILEGES would be considered DCL commands, I do believe they replicate within Galera since they modify the privileges tables and force an update of the grant cache on each node. In fact they do, you can see “mode: toi” in the error log messages above.
DESCRIBE is local, but requires checking permissions so there seems to be some race-condition/conflict when these are ran concurrently.
Why does your application need to DESCRIBE tables all the time? Is your schema not static? A constantly changing schema is typically considered a bad practice in a production environment.

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