innodb_buffer_pool_dump_pct
INFO
Rule IDs: bp_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 dynamic (
Dynamic= Yes). Runtime changes useSET GLOBAL(global scope) orSET SESSION(session scope) — confirm syntax and persistence (SET PERSIST) in the manual. - Default value
- 25 (MySQL 8.4)
- 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_buffer_pool_dump_pct
- Other vendors
What is checked
Rules that reference this variable, with their severity and what each rule detects:
- INFO
bp_009: Consider innodb_buffer_pool_dump_pct=75 when using dump/load at shutdown/startup for faster cache warm-up without dumping the entire pool.
Tuning guidance
- Recommended actions:
- Consider innodb_buffer_pool_dump_pct=75 when using dump/load at shutdown/startup for faster cache warm-up without dumping the entire pool.
- Trade-offs: Larger buffer pools improve hit ratio but consume more RAM and increase restart warm-up time. Over-allocating risks OOM or swap. Under-allocating means more disk I/O.
Example
Consult the manual for whether SET GLOBAL, SET PERSIST, or SET SESSION applies.