wsrep_slave_threads
INFO
Rule IDs: pxc_005
Overview
- Purpose
- Galera Cluster / Percona XtraDB Cluster:
wsrep_*names usually refer to status or wsrep-related configuration documented for MariaDB Galera Cluster or Percona XtraDB Cluster, not standard standalone MySQL 8.4 dynamic variables in the Oracle reference. - Dynamic (MySQL 8.4 reference)
- Consult MariaDB Galera and Percona XtraDB Cluster documentation for the exact item (status vs
SET/wsrep_provider_options). - Default value
- See cluster vendor docs.
- Version and product notes
- Not covered by the MySQL 8.4 server variable summary table shipped in
scripts/data/. - Documentation
- Primary reference depends on product (MySQL, MariaDB, Percona, or OS documentation).
- Vendor documentation
What is checked
Rules that reference this variable, with their severity and what each rule detects:
- INFO
pxc_005: Set wsrep_slave_threads to approximately wsrep_cert_deps_distance (rounded). Too many threads add overhead without benefit.
Tuning guidance
- Recommended actions:
- Set wsrep_slave_threads to approximately wsrep_cert_deps_distance (rounded). Too many threads add overhead without benefit.
- Trade-offs: Galera cluster settings affect write throughput, consistency, and failover behavior. Flow control protects slow nodes but can stall the entire cluster. SST method choice affects donor impact during node joins.
Example
Follow Percona / MariaDB cluster administration guides.