MySQL Tweaking

After setting up WordPress and another MySQL-based application on my OpenBSD 3.6 server and then referencing a link to my website on OpenBSD's misc @, MySQL kept dying. The biggest problem with that was: WordPress's database errors occurred prior to HTML headers being sent. So, I never saw any reference to any errors until using curl to download the page.

To fix the problem, I googled and searched the misc @ archives. I found several references to mysql problems and the solution finally came down to the following:

• Editing the /etc/login.conf file, adding this section:
mysql:\
:datasize=infinity:\
:maxproc=infinity:\
:openfiles-cur=2048:\
:openfiles-max=8192:\
:stacksize-cur=8M:\
:localcipher=blowfish,8:\
:tc=default:



• Then, I added an /etc/my.cnf (MySQL config file) with these contents:
[mysqld]
set-variable = max_allowed_packet=64M
set-variable = max_connections=1000
[mysqld-safe]
open-files = 2048



• Finally, I changed the MySQL startup command in /etc/rc.local to:
sudo -c mysql -u _mysql /usr/local/share/mysql/mysql.server start
sudo -c mysql /usr/local/share/mysql/mysql.server start
[Edit: (2005-04-04 @ 7:15 PM ET) It seems that starting MySQL from /etc/rc.local with sudo -u _mysql caused MySQL not to start, so I removed the "-u _mysql"]

To aid in starts, stops and re-starts, I made aliases in my /etc/profile:

mysql-restart='sudo sudo -c mysql -u _mysql /usr/local/share/mysql/mysql.server restart'

mysql-start='sudo sudo -c mysql -u _mysql /usr/local/share/mysql/mysql.server start'

mysql-stop='sudo sudo -c mysql -u _mysql /usr/local/share/mysql/mysql.server stop'

Note the double sudo. When I didn't run "sudo sudo ...", I got a message saying that only root could launch a command with sudo and "-c class". The double sudo fixed that. My user account is in the wheel group which, in the /etc/sudoers, is allowed to run any command as root (as long as members authenticate with their password).