Hi @stofa.kenida,
I believe your restart test confirms what Yunus pointed to, the 478 rows are not the problem, it’s the mutex_instances table behind them ( PXC-5310, still open ).
One thing from the PMM side, as nobody mentioned it yet. This query is not coming from QAN, it’s the perf_schema.eventswaits collector of mysqld_exporter, and it runs every 10 sec. So switching query source from perfschema to slowlog will not remove it, you can keep perfschema.
You can disable only this collector and keep the rest, it needs remove and add of the service:
pmm-admin remove mysql <service-name>
pmm-admin add mysql --query-source=perfschema --disable-collectors=perf_schema.eventswaits --username=pmm --password=... --service-name=<service-name>
You will lose only the Performance Schema Wait Events panels on the MySQL dashboards. Till the fix is out, a restart on maintenance window is what clears it ( performance_schema_max_mutex_instances also needs restart, there is more on this in PXC 8.4.6: LOCK_ticket_store_ops mutex instances grow with cumulative connections ).