Can't set MySQL max_connections

[Ian Wells]

max_connections can't be changed using the mysql puppet module. Necessary if you increase parallelism.

[Mark T. Voelker (mvoelker)]

This is basically a feature request since it asks for new functionality.

[Mark T. Voelker (mvoelker)]

Note: upstream now has this (and a whole lot of other things, so it'll need some testing).

[Mark T. Voelker (mvoelker)]

Due to the change to the new data model in h.0 and accompanying update to the mysql module (also in h.0), this can now be set by setting the following either in user.common.yaml or in a host override file (substitute the number of connections you want to allow in place of "200" below):

mysql::config::max_connections: 200

[Ken Schroeder (kschroed)]

This does not appear fixed in Icehouse.1 proposed

hiera_data/user.common.yaml contains
mysql::server::override_options:
  mysqld:
    bind-address: 10.114.196.11
    max-connections: 8192
    max_connect_errors: 4294967295
  isamchk:
    key_buffer_size: 64M

Deployed Mysql server contains.
root@svl4-csm-b-aio-001:~# grep -r max /etc/mysql/*
/etc/mysql/my.cnf:max_allowed_packet = 16M
/etc/mysql/my.cnf:max_binlog_size = 100M
/etc/mysql/my.cnf:max_connections = 151
/etc/mysql/my.cnf:max_allowed_packet = 16M

[Mark T. Voelker (mvoelker)]

Hmm...works for me:

localadmin@compute01:~$ grep -A6 'override_options:' /etc/puppet/data/hiera_data/user.common.yaml
mysql::server::override_options:
  mysqld:
    bind-address: 192.168.255.134
    max-connections: 8192
    max_connect_errors: 4294967295
  isamchk:
    key_buffer_size: 64M
localadmin@compute01:~$ grep max-connections /etc/mysql/my.cnf
max-connections = 8192
localadmin@compute01:~$

mysql> show variables where Variable_name = 'max_connections';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| max_connections | 8192 |
+-----------------+-------+
1 row in set (0.00 sec)

mysql>

[Mark T. Voelker (mvoelker)]

Ah. It didn't work for you because you were in a compressed_ha scenario (for those tuning in at home, see https://bugs.launchpad.net/bugs/1352095).