CCIE那点事

项目中，由于连接数过多，提示“Too many connections”，需要增加连接数。我在 /etc/my.cnf中修改了

max_connections = 3000

但是， 一直都是显示的 214

mysql> show variables like "max_connections";
+—————–+——-+
| Variable_name   | Value |
+—————–+——-+
| max_connections | 214   |
+—————–+——-+
1 row in set+

修改 /usr/lib/systemd/system/mariadb.service
LimitNOFILE=65535
LimitNPROC=65535

systemctl status mariadb

Warning: mariadb.service changed on disk. Run ‘systemctl daemon-reload’ to reload units.
Hint: Some lines were ellipsized, use -l to show in full.

systemctl daemon-reload
systemctl restart mariadb

show variables like ‘%max_connections%’;

extra_max_connections    1
max_connections    3000    —恢复和配置一样

———————————————4190－－－－－－－－－－－－－－－
mysql max_connections 总是    4190
Variable_name    Value
max_connections    4190

查mysql open files
show global variables like ‘%open_files_limit%’;
Variable_name    Value
open_files_limit    5000

所以max_connections 不管设多大，都小于5000

－－－－－解决
修改本地openfiles值

到/etc/security/limits.conf這個檔案。

/etc/security/limits.conf
* soft nofile 65536
* hard nofile 65536

查看本地open files
ulimit -a |grep open
open files                      (-n) 555550

查看
grep LimitNOFILE /usr/lib/systemd/system/mysqld.service
LimitNOFILE = 5000
修改
grep LimitNOFILE /usr/lib/systemd/system/mysqld.service
LimitNOFILE = 50000

reload
Warning: mysqld.service changed on disk. Run ‘systemctl daemon-reload’ to reload units.

重启
systemctl restart mysqld
验证
grep max_connections /etc/my.cnf
max_connections=32000

show VARIABLES like "max_connections"
Variable_name    Value
max_connections    32000

修改值与mysql值一致