Ubuntu MySQL – How to Fix my.cnf Ignored Issue

my.cnfMySQLUbuntuubuntu-10.04ubuntu-11.10

The Issue

I'm trying to modify a my.cnf value on my production server but the changes aren't taking effect after a sudo service mysql restart, using an exact copy of the my.cnf (downloaded and replaced original) on my development server the changes made are visible from show variables in mysql commandline.

my.cnf is located at /etc/mysql/my.cnf

sudo find / -name my.cnf
/etc/mysql/my.cnf

So only one file exists on the entire system..

Production is ubuntu 10.04 LTS 64bit
Development is ubuntu 11.10 32bit

Mysql versions are 5.1.61 & 5.1.62 respectively.

Update 2 :

After running mysql stop and mysql status return mysql stop/waiting, if i run top -b | grep mysql

27652 root      20   0  4096  424  420 S    0  0.0   0:00.01 mysqld_safe
27769 mysql     20   0  392m  57m 7236 S    0  1.5 119116,08 mysqld

This looks like its still running and the time doesnt look good to me, but I'm now worried if i kill these/this process I wont be able to get mysql running again, and being production this is bad :S.

I realise it's probably not something that can be answered but killing these processes and then running service mysql start, will this have mysql running again? – Also, do the proccesses above have normal numbers for them?

Update:

Doesn't this imply its getting the settings from my.cnf… but not using it? So very confused right now.
At the end its got the innodb_buffer.. settings.

mysqld --print-defaults
mysqld would have been started with the following arguments:
--user=mysql --socket=/var/run/mysqld/mysqld.sock --port=3306 --basedir=/usr --datadir=/var/lib/mysql --tmpdir=/tmp --skip-external-locking --bind-address=127.0.0.1 --key_buffer=16M --max_allowed_packet=16M --thread_stack=192K --thread_cache_size=8 --myisam-recover=BACKUP --query_cache_limit=1M --query_cache_size=16M --log_error=/var/log/mysql/error.log --expire_logs_days=9 --max_binlog_size=100M --innodb_file_per_table=1 --innodb_buffer_pool_size=500M --innodb_buffer_pool_size=500M --user=mysql --socket=/var/run/mysqld/mysqld.sock --port=3306 --basedir=/usr --datadir=/var/lib/mysql --tmpdir=/tmp --skip-external-locking --bind-address=127.0.0.1 --key_buffer=16M --max_allowed_packet=16M --thread_stack=192K --thread_cache_size=8 --myisam-recover=BACKUP --query_cache_limit=1M --query_cache_size=16M --log_error=/var/log/mysql/error.log --expire_logs_days=9 --max_binlog_size=100M --innodb_file_per_table=1 --innodb_buffer_pool_size=500M --innodb_buffer_pool_size=500M

my.cnf

[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
user        = mysql
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
skip-external-locking
bind-address        = 127.0.0.1
key_buffer      = 16M
max_allowed_packet  = 16M
thread_stack        = 192K
thread_cache_size       = 8
myisam-recover         = BACKUP
query_cache_limit   = 1M
query_cache_size        = 16M
log_error                = /var/log/mysql/error.log
expire_logs_days    = 10
max_binlog_size         = 100M
innodb_file_per_table = 1

[mysqldump]
quick
quote-names
max_allowed_packet  = 16M

[mysql]

[isamchk]
key_buffer      = 16M

!includedir /etc/mysql/conf.d/

Best Answer

Anything interesting in /etc/mysql/conf.d/? The version of Mysql you're using should parse my.cnf then, anything in /etc/mysql/conf.d/ in order of the config file names. In previous versions the order could be somewhat non deterministic.

Whatever value is set last in the chain should win, which might explain why your changes in my.cnf aren't updating the server; If later files are overriding your settings.

If there is nothing in /etc/mysql/conf.d/ for the hell of it create a file called innodb.cnf (won't parse anything that doesn't end in .cnf) with only these two lines and see if your innodb setting updates after a restart.

[mysqld]
innodb_buffer_pool_size = 500M

Info From Docs:

username$ mysqld --verbose --help | grep '/my.cnf' -B 1

Default options are read from the following files in the given order:
/etc/my.cnf 
/etc/mysql/my.cnf 
/usr/local/mysql/etc/my.cnf 
~/.my.cnf

and details of this are in the MySQL Docs Look under Table 4.2

It is possible to use !include directives in option files to include other option files and !includedir to search specific directories for option files.....

...MySQL makes no guarantee about the order in which option files in the directory will be read...

Any files to be found and included using the !includedir directive on Unix operating systems must have file names ending in .cnf. On Windows, this directive checks for files with the .ini or .cnf extension.

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