Mysql “分析连接以进行诊断”；“连接太多”；错误

我的网站当前收到以下错误消息：

建立数据库连接时出错

。如果我打开/phpma，我会收到以下信息：

#1040-连接太多

如果重新启动mysqld，问题会暂时消失

不幸的是，它现在又出现了三次

我的专用存储箱的内存也从8Gb降至1Gb以下

Total Memory    8181984 kB
Free Memory 99344 kB
Total Swap Memory   1051064
kB Free Swap Memory 0 kB

如果我进入服务器上的

mysql

并执行

SHOW PROCESSLIST

，我会收到以下信息：

| 17181 | my_db | localhost | my_db | Query   | 35117 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'boraras-brigittae' AND wp_po |
| 17182 | my_db | localhost | my_db | Query   | 35118 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17183 | my_db | localhost | my_db | Query   | 35117 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'boraras-brigittae' AND wp_po |
| 17184 | my_db | localhost | my_db | Query   | 35117 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'boraras-brigittae' AND wp_po |
| 17185 | my_db | localhost | my_db | Query   | 35041 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'akysis-vespa' AND wp_posts.p |
| 17186 | my_db | localhost | my_db | Query   | 35050 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('images','profiledotline-gif') A |
| 17187 | my_db | localhost | my_db | Query   | 35050 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('images','picarrow-gif') AND (po |
| 17188 | my_db | localhost | my_db | Query   | 35043 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17189 | my_db | localhost | my_db | Query   | 35041 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('m','marginal') AND (post_type = |
| 17190 | my_db | localhost | my_db | Query   | 34989 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17191 | my_db | localhost | my_db | Query   | 34989 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('w','wet-dry-filter') AND (post_ |
| 17192 | my_db | localhost | my_db | Query   | 34990 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17193 | my_db | localhost | my_db | Query   | 34954 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'corydoras-sterbai' AND wp_po |
| 17194 | my_db | localhost | my_db | Query   | 34954 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17195 | my_db | localhost | my_db | Query   | 34955 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17196 | my_db | localhost | my_db | Query   | 34954 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17197 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17198 | my_db | localhost | my_db | Query   | 34955 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17199 | my_db | localhost | my_db | Query   | 34898 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17200 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17201 | my_db | localhost | my_db | Query   | 34898 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums','lofiversion','index-ph |
| 17202 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17204 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17205 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'sawbwa-resplendens' AND wp_p |
| 17206 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'badis-sp-buxar' AND wp_posts |
| 17207 | my_db | localhost | my_db | Query   | 34898 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'melanotaenia-boesemani' AND  |
| 17208 | my_db | localhost | my_db | Query   | 34898 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'betta-prima' AND wp_posts.po |
| 17209 | my_db | localhost | my_db | Query   | 34865 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17210 | my_db | localhost | my_db | Query   | 34897 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17211 | my_db | localhost | my_db | Query   | 34898 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17213 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17214 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17215 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('knowledge-base') AND (post_type |
| 17216 | my_db | localhost | my_db | Query   | 34865 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17217 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17218 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'badis-sp-buxar' AND wp_posts |
| 17219 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums','lofiversion','index-ph |
| 17220 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'betta-prima' AND wp_posts.po |
| 17221 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17222 | my_db | localhost | my_db | Query   | 34865 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17223 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17224 | my_db | localhost | my_db | Query   | 34865 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'hemichromis-lifalili' AND wp |
| 17225 | my_db | localhost | my_db | Query   | 34864 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17226 | my_db | localhost | my_db | Query   | 34862 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'apistogramma-borellii' AND w |
| 17227 | my_db | localhost | my_db | Query   | 34863 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'melanotaenia-lacustris' AND  |
| 17228 | my_db | localhost | my_db | Query   | 34862 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'melanotaenia-lacustris' AND  |
| 17229 | my_db | localhost | my_db | Query   | 34861 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'mikrogeophagus-altispinosus' |
| 17230 | my_db | localhost | my_db | Query   | 34861 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.ID = 25503 AND wp_posts.post_type = 'atta |
| 17231 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'piaractus-brachypomus' AND w |
| 17232 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17233 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('knowledge-base') AND (post_type |
| 17234 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17235 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17236 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17237 | my_db | localhost | my_db | Query   | 34803 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17238 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('m','migrate') AND (post_type =  |
| 17239 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'hemichromis-lifalili' AND wp |
| 17240 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17241 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17242 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17243 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17244 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums','lofiversion','index-ph |
| 17245 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17246 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT post_modified_gmt FROM wp_posts WHERE post_status = 'publish' AND post_type IN ('post', 'page |
| 17247 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 17248 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'geophagus-brokopondo' AND wp |
| 17249 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT   wp_posts.* FROM wp_posts  WHERE 1=1  AND wp_posts.post_name = 'hyphessobrycon-amandae' AND  |
| 17253 | my_db | localhost | my_db | Query   | 34788 | Waiting for table level lock | SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts  WHERE 1=1  AND wp_posts.post_type = 'post' AN |
| 17255 | my_db | localhost | my_db | Query   | 34786 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('knowledge-base') AND (post_type |
| 17260 | my_db | localhost | my_db | Query   | 34786 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('s','silver-sand') AND (post_typ |
| 17262 | my_db | localhost | my_db | Query   | 34786 | Waiting for table level lock | SELECT ID, post_name, post_parent FROM wp_posts WHERE post_name IN ('forums') AND (post_type = 'page |
| 25505 | root      | localhost | NULL      | Query   |     2 | NULL                         | SHOW PROCESSLIST                                                                                     

我尝试使用

--log slow querys[slow querys]

标志运行

mysql

，但它似乎没有做任何事情-至少在我的框中的任何地方都找不到名为

slow querys

的文件

我猜这是一个可疑的查询，但我不知道从哪里开始寻找

---

编辑：点击和设置

• MySQL目前最多同时运行500个连接
• PHP的内存限制非常高（大约1Gb），因为我正在尝试对脚本进行一些性能测试
• 仅此一个网站（盒子上还有其他网站；所有网站目前都受到此错误的影响）每周就收到约30000个独立访问者和250000次点击

---

根据我的经验，在高负载水平下，wordpress（我假设它是基于表名的wordpress）对于慢速查询是相当糟糕的。一旦表达到一定大小（这里的post表是一个主要问题），查询就会变得非常慢，您需要进行优化以跟上速度

在MySQL优化术语中，它与分配给缓冲区和MySQL查询缓存的内存有关，因为wordpress尽可能多地从数据库中卸载内存

从堆栈的顶部到底部，您可以做一些不同的事情：

Wordpress优化。删除未使用的插件，添加页面缓存（W3 Total Cache是金标准），简言之，从数据库中尽可能多地卸载。此外，还可以减少为每篇文章存储的“修订”数量（）。对于一个有5年历史的站点，您可能有比帖子多得多的修订，这将降低帖子查找的速度（代码段中的查询都是帖子查找）

MySQL优化。这是一个棘手的问题，因为有一大堆的刻度盘你可以调整，找到正确的平衡是一种黑暗的艺术。有很多文章和教程在那里，我没有任何具体的建议，但一个简单的谷歌会抛出很多关于你可以对你的my.cnf文件进行调整的信息

---

您可以尝试以下方法来捕获慢速查询：

在/etc/my.cnf文件中，它是mysql配置文件

将这两行放在[mysqld]节下

slow_query_log_file=/var/log/mysql-log-slow-queries.log
long_query_time=2

---

希望能有所帮助。

此网站每秒的点击率是多少？如果你提高连接限制，问题是会消失还是会持续更长的时间？我已将此信息添加到我的OP中。随着网站的建立，Maxu connections已经是大约5年的默认值，但这几乎是一夜之间突然发生的。昨晚我把max_connections设置提高到了500，今天早上醒来时也出现了同样的问题。这个网站在WordPress上只运行了2个月左右。自从它上线以来，我只允许每篇文章修改3次。公平的说，其他几点仍然有效——我曾经管理一个由25多个流行wordpress网站组成的网络，每周有30000个uniques，我过去经常遇到问题，需要查看缓存和mysql调优。好吧，很酷。我发现了一些调整脚本，所以我现在正试图破解它们。谢谢