Question

我在Ubuntu Server 5.6上使用MySQL 14.04，并希望增加最大允许同时连接数（当前设置为默认151）。

对此max_connections中的/etc/mysql/my.cnf设置负责。所以我将其设置为200并重新启动MySQL服务器。现在，它的值为200：

$ cat /etc/mysql/my.cnf | grep "connections"
max_connections        = 200
$ /etc/init.d/mysql restart
 * Stopping MySQL database server mysqld                                                                                             [ OK ] 
 * Starting MySQL database server mysqld                                                                                             [ OK ] 
 * Checking for tables which need an upgrade, are corrupt or were 
not closed cleanly.

但一切都没有改变：

SHOW VARIABLES LIKE "max_connections";
+-----------------+-------+
¦ Variable_name   ¦ Value ¦
+-----------------+-------+
¦ max_connections ¦ 151   ¦
+-----------------+-------+

如何让max_connections的自定义配置正常工作？

$ ulimit -a | grep "open"
open files                      (-n) 1024
$ ulimit -n 4096
$ ulimit -a | grep "open"
open files                      (-n) 4096

添加到/etc/security/limits.conf：

* soft nofile 1024000
* hard nofile 1024000
* soft nproc 10240
* hard nproc 10240
root soft nproc unlimited

添加到/etc/mysql/my.cnf：

[mysqld_safe]
open_files_limit = 1024000
[mysqld]
open_files_limit = 1024000

但它似乎被忽略了：

SHOW STATUS LIKE 'open%';
+--------------------------+-------+
¦ Variable_name            ¦ Value ¦
+--------------------------+-------+
¦ Open_files               ¦ 52    ¦
+--------------------------+-------+
¦ Open_streams             ¦ 0     ¦
+--------------------------+-------+
¦ Open_table_definitions   ¦ 434   ¦
+--------------------------+-------+
¦ Open_tables              ¦ 417   ¦
+--------------------------+-------+
¦ Opened_files             ¦ 847   ¦
+--------------------------+-------+
¦ Opened_table_definitions ¦ 0     ¦
+--------------------------+-------+
¦ Opened_tables            ¦ 0     ¦
+--------------------------+-------+

为了避免在错误的文件中设置正确的配置，我在所有这些文件中设置了选项（其中一些不存在，所以我创建了它们）：

$ mysqld --help --verbose | grep -B 1 cnf
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf

没效果。

Answer 1

您必须增加操作系统上的打开文件限制，然后，您可以设置更高的max_connections值。

Answer 2

[mysqld]

max_connections = 400

MAX_USER_CONNECTIONS = 300

你必须将max_connections属性添加到[mysqld]中。对我而言......

如何在Ubuntu Server上增加MySQL的max_connections值？

2 个答案: