innodb_sync_array_size
INFO
Rule IDs: cc_009
Overview
- Purpose
- Documented in the MySQL 8.4 manual as a server system variable (scope: Global). Purpose and semantics are described at the linked manual page.
- Dynamic (MySQL 8.4 reference)
- MySQL 8.4 marks this variable as not dynamic (
Dynamic= No). It must be set inmy.cnfor on the command line; changing it requires a restart. - Default value
- Default depends on MySQL version, build, and platform — see the manual page for this variable.
- Version and product notes
- MariaDB and Percona Server may use different names, defaults, or dynamic behavior; verify their documentation.
- Documentation
- https://dev.mysql.com/doc/refman/8.4/en/innodb-parameters.html#sysvar_innodb_sync_array_size
- Other vendors
What is checked
Rules that reference this variable, with their severity and what each rule detects:
- INFO
cc_009: On multi-core servers with high concurrency, consider innodb_sync_array_size=4 to spread waits across more sync cells (requires restart).
Tuning guidance
- Recommended actions:
- On multi-core servers with high concurrency, consider innodb_sync_array_size=4 to spread waits across more sync cells (requires restart).
- Trade-offs: Thread concurrency controls balance CPU utilization against contention. Too many concurrent threads cause lock waits; too few leave CPU idle. Auto-management (concurrency=0) works well for most workloads.
Example
Configure in my.cnf (or equivalent) or server startup options, then restart.