深入MySQL调优原则

mysql soft nofile 65535
mysql hard nofile 65535

fs.file-max = 1000000

sysctl -p

[mysqld]
innodb_buffer_pool_size = 4G  # 调整缓冲池大小
query_cache_size = 256M  # 调整查询缓存大小

[mysqld]
max_connections = 1000  # 调整最大连接数
thread_cache_size = 50  # 调整线程缓存大小

[mysqld]
innodb_log_file_size = 512M  # 调整日志文件大小
innodb_flush_log_at_trx_commit = 1  # 设置日志刷新策略

[mysqld]
table_open_cache = 2000  # 调整表缓存大小

CREATE INDEX idx_user_id ON users(user_id);

CREATE INDEX idx_user_status ON users(user_id, status);

CREATE TABLE orders (
    order_id INT NOT NULL,
    order_date DATE NOT NULL,
    customer_id INT NOT NULL,
    amount DECIMAL(10, 2) NOT NULL
)
PARTITION BY RANGE (YEAR(order_date)) (
    PARTITION p0 VALUES LESS THAN (1990),
    PARTITION p1 VALUES LESS THAN (2000),
    PARTITION p2 VALUES LESS THAN (2010),
    PARTITION p3 VALUES LESS THAN (2020)
);

EXPLAIN SELECT * FROM users WHERE user_id = 12345;

SELECT * FROM users USE INDEX (idx_user_id) WHERE user_id = 12345;

-- 原始复杂查询
SELECT * FROM orders WHERE amount > 1000 AND order_date BETWEEN '2022-01-01' AND '2022-12-31';

-- 分解为简单查询
SELECT order_id FROM orders WHERE amount > 1000;
SELECT * FROM orders WHERE order_id IN (SELECT order_id FROM orders WHERE amount > 1000) AND order_date BETWEEN '2022-01-01' AND '2022-12-31';

wget http://mysqltuner.pl/ -O mysqltuner.pl
chmod +x mysqltuner.pl
./mysqltuner.pl

[mysqld]
innodb_buffer_pool_size = 8G  # 根据建议调整缓冲池大小
query_cache_size = 512M  # 根据建议调整查询缓存大小