Daemons causing Mysql::Error:Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'

Hi all,

Ive been having this problem for the past few days on production. I have a couple of daemons (using the daemons gem and daemon_generator) that I run every hour on the server. One of them sends out email too (just in case thats relevant information). Besides this, I have 4 Rails apps running on the server one of which contains the above mentioned daemons.

Now everytime I deploy, I have a couple of Capistrano tasks that stop the daemons before:update_code and start them again after:update_code. This I do because they stop running altogether during the deployment window because MySQL locks down and the daemons, when trying to connect to MySQL, fail.

However, once both daemons are started, everything funcitons fine for about 15-20 minutes after which, if I try to access any of the 4 Rails apps, I get "Mysql::Error:Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'". I also sometimes get the "MySQL server has gone away" error. I especially get the 2nd error in the daemons logs when they try to run again. Sometimes, when I try to access one of my apps, Passenger throws an error saying

Passenger::Railz::ApplicationSpawner::Error application_spawner.rb line 111 in `spawn_ application'

Now all these are related only to the daemons cos if I stop them and reboot my server, the apps work just great. Googling around, I found that the "MySQL server has gone away" error can be fixed by adding

  ActiveRecord::Base.connection.reconnect!

just before running AR queries from daemons. I tried it but it dint stop the apps from crashing. Is the connection apparent to anyone? Any ideas on how I can resolve this with least impact on my 4 apps running on production??

Ummm. Maybe I should cut the long story short.

couple of daemons, when running on server, slow down and crash my Rails apps. Logs show me errors like

Mysql::Error:Can't connect to local MySQL server through socket '/var/ run/mysqld/mysqld.sock' & MySQL server has gone away

Sometimes, I also get a Passenger::Railz::ApplicationSpawner::Error. Any ideas on what might be going wrong? Tried "ActiveRecord::Base.connection.reconnect! " in the daemons but that dint help.