What does it mean?

First indication is that your server is out of memory. Then mysql service was restarted but it haven’t enough memory start again and it stuck in that process. First look on current status of your server, investigate memory consumption.

Next you need to be sure that mysql user (default user that is used for mysql service has appropriate rights for sock file and mysqld folder).

My problem was with mysql.sock file since mysql user was not able to delete or modify content of sock file regularly. So I changed my sock file to /tmp folder and everything works fine, of course you need to restart your mysqld service.

To change path of sock file go to /etc/my.conf and under line starting with “sock” add correct value and if there are no lines in your my.conf file for client please add them :

[client]
socket = /tmp/mysql.sock

go to mysql console ( mysql -u root -p YOURPASSWORD) and hit “status”, watch on last line

Threads: 1 Questions: 1428 Slow queries: 0 Opens: 58 Flush tables: 1 Open tables: 51 Queries per second avg: 7.000

and look for value of Queries per second avg. Try to reduce this value as much as possible since that is the number of queries that your apps are hitting to mysql.

Of course restart your mysqld service with line “mysql service restart”