mysql 每天在同一时间变得无响应

Question

我的服务器每天都在同一时间停机。我发现问题是由于mysql。

我试过显示进程列表；并发现数据库正在进入睡眠模式。我看到 log_url 表中有很多插入，如下所示

mysql> show processlist;
+-------+---------------+-----------+------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| Id    | User          | Host      | db               | Command | Time | State        | Info                                                                                                 |
+-------+---------------+-----------+------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| 72962 | sonicsense_db | localhost | sonicsense_db    | Query   |    1 | Sending data | SELECT `log_url`.* FROM `log_url` LIMIT 2381 OFFSET 2992917                                          |
| 74069 | sonicsense_db | localhost | sonicsense_db    | Query   |    4 | Updating     | UPDATE `cron_schedule` SET `job_code` = 'captcha_delete_expired_images', `status` = 'error', `messag |
| 74073 | sonicsense_db | localhost | sonicsense_db    | Query   |   51 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528425', '4646727', '2013-08- |
| 74074 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   52 |              | NULL                                                                                                 |
| 74077 | sonicsense_db | localhost | sonicsense_db    | Query   |   41 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528426', '4646728', '2013-08- |
| 74078 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   42 |              | NULL                                                                                                 |
| 74079 | sonicsense_db | localhost | sonicsense_db    | Query   |   36 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528427', '4646729', '2013-08- |
| 74080 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   37 |              | NULL                                                                                                 |
| 74081 | sonicsense_db | localhost | sonicsense_db    | Query   |   34 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528428', '4646730', '2013-08- |
| 74082 | sonicsense_db | localhost | sonicsense_db    | Query   |   31 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528429', '4646731', '2013-08- |
| 74084 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   32 |              | NULL                                                                                                 |
| 74085 | sonicsense_db | localhost | sonicsense_db    | Query   |   30 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528430', '4646732', '2013-08- |
| 74086 | sonicsense_db | localhost | sonicsense_db    | Query   |   31 | Updating     | UPDATE `catalogsearch_query` SET `query_text` = 'PreSonus', `num_results` = '154', `popularity` = '3 |
| 74087 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   31 |              | NULL                                                                                                 |
| 74088 | sonicsense_db | localhost | sonicsense_db    | Query   |   20 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528431', '4646734', '2013-08- |
| 74089 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   20 |              | NULL                                                                                                 |
| 74090 | sonicsense_db | localhost | sonicsense_db    | Query   |   12 | update       | INSERT IGNORE INTO core_cache_tag (tag, cache_id) VALUES ('MAGE_cache_DEFAULT', 'MAGE_cache_LAYOUT_1 |
| 74091 | sonicsense_db | localhost | sonicsense_db    | Query   |   10 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528432', '4646736', '2013-08- |
| 74092 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   11 |              | NULL                                                                                                 |
| 74093 | sonicsense_db | localhost | sonicsense_db    | Query   |    9 | update       | INSERT INTO `log_url` (`url_id`, `visitor_id`, `visit_time`) VALUES ('6528433', '4646737', '2013-08- |
| 74094 | sonicsense_db | localhost | sonicsense_wp_db | Sleep   |   10 |              | NULL                                                                                                 |
| 74095 | sonicsense_db | localhost | NULL             | Query   |    0 | NULL         | show processlist                                                                                     |
+-------+---------------+-----------+------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+

重启 mysql 解决了我的问题。我如何检测是什么导致了如此多的插入以及为什么我的数据库进入睡眠模式。

我也尝试查看mysql日志，发现以下错误1）最后一个检查点的年龄为9433987，InnoDB：超过了日志组容量9433498。

2) 无法使用 /var/log/mysql/mysql.log 进行日志记录（错误 2）。关闭整个注销

我今天又试了一次，发现下面的数据库处于睡眠模式

63211   sonicsense_db   localhost       sonicsense_wp_db        Sleep   49              NULL
63215   sonicsense_db   localhost       sonicsense_wp_db        Sleep   37              NULL
63217   sonicsense_db   localhost       sonicsense_wp_db        Sleep   37              NULL
63219   sonicsense_db   localhost       sonicsense_wp_db        Sleep   36              NULL
63221   sonicsense_db   localhost       sonicsense_wp_db        Sleep   16              NULL

有谁知道我如何解决由于 mysql 导致的站点崩溃问题。

我启用了慢查询日志，我得到了以下详细信息

/usr/libexec/mysqld, Version: 5.1.69-log (Source distribution). started with:
Tcp port: 0  Unix socket: /var/lib/mysql/mysql.sock
Time                 Id Command    Argument
/usr/libexec/mysqld, Version: 5.1.69-log (Source distribution). started with:
Tcp port: 0  Unix socket: /var/lib/mysql/mysql.sock
Time                 Id Command    Argument
/usr/libexec/mysqld, Version: 5.1.69-log (Source distribution). started with:
Tcp port: 0  Unix socket: /var/lib/mysql/mysql.sock
Time                 Id Command    Argument
/usr/libexec/mysqld, Version: 5.1.69-log (Source distribution). started with:
Tcp port: 0  Unix socket: /var/lib/mysql/mysql.sock
Time                 Id Command    Argument

仍然找不到任何原因为什么 mysql 每天都在同一时间变得无响应

Answer 1

编辑/etc/mysql/my.cnf配置并添加：

    log_slow_queries = /var/log/mysql/mysql-slow.log
    long_query_time  = 2

第一行启用慢查询日志（记得旋转它），第二行是关于查询必须至少需要多少秒才能被视为慢查询。

启用此功能后，您可以开始调查哪些查询明显减慢了 MySQL 实例的速度。