MySQL Conf

mysqld --verbose --help
mysqld --no-defaults --verbose --help

SHOW VARIABLES;

select * from performance_schema.persisted_variables;
select * from performance_schema.global_variables;

mysqld

--character-set-server=utf8mb4
--collation-server=utf8mb4_unicode_ci
--max-connections=2000

• my.cnf
• --defaults-extra-file
• .mylogin.cnf
  • --no-defaults
• mysqld-auto.cnf
  • persisted_globals_load
  • SET PERSIST
• mysql_config_editor
• 参考
  • MySQL Log
  • https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html
  • https://dev.mysql.com/doc/refman/8.0/en/option-files.html

配置方式

启动参数配置

mysqld --sort-buffer-size=256K --max-allowed-packet=1G

my.cnf

[mysqld]
sort_buffer_size=256K
max_allowed_packet=1G

动态配置

SET GLOBAL max_connections = 1000;
SET @@GLOBAL.max_connections = 1000;

-- mysqld-auto.cnf
SET PERSIST max_connections = 1000;
SET @@PERSIST.max_connections = 1000;

-- 不修改当前
SET PERSIST_ONLY back_log = 1000;
SET @@PERSIST_ONLY.back_log = 1000;

-- 会话维度
SET SESSION sql_mode = 'TRADITIONAL';
SET @@SESSION.sql_mode = 'TRADITIONAL';
SET @@sql_mode = 'TRADITIONAL';

query_cache_size

• 8.0 移除
• 5.6 禁用
• https://dba.stackexchange.com/a/217578/234272