MySQL定位锁争用比较严重的表

1：查看当前的事务

mysql> SELECT * FROM information_schema.innodb_trx \G

2：查看当前锁定的事务

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCKS;

3：查看当前等锁的事务

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS;

SELECT
    r.trx_id waiting_trx_id,
    r.trx_mysql_thread_id waiting_thread,
    TIMESTAMPDIFF(
        SECOND,
        r.trx_wait_started,
        CURRENT_TIMESTAMP
    ) wait_time,
    r.trx_query waiting_query,
    l.lock_table waiting_table_lock,
    b.trx_id blocking_trx_id,
    b.trx_mysql_thread_id blocking_thread,
    SUBSTRING(
        p. HOST,
        1,
        INSTR(p. HOST, ':') - 1
    ) blocking_host,
    SUBSTRING(p. HOST, INSTR(p. HOST, ':') + 1) blocking_port,  

IF (p.COMMAND = 'Sleep', p.TIME, 0) idel_in_trx,
 b.trx_query blocking_query
FROM
    information_schema.INNODB_LOCK_WAITS w
INNER JOIN information_schema.INNODB_TRX b ON b.trx_id = w.blocking_trx_id
INNER JOIN information_schema.INNODB_TRX r ON r.trx_id = w.requesting_trx_id
INNER JOIN information_schema.INNODB_LOCKS l ON w.requested_lock_id = l.lock_id
LEFT JOIN information_schema. PROCESSLIST p ON p.ID = b.trx_mysql_thread_id
ORDER BY
    wait_time DESC;