MySQL server has gone away fix

connection_fix.rb

# If your workers are inactive for a long period of time, they'll lose
# their MySQL connection.
#
# This hack ensures we re-connect whenever a connection is
# lost. Because, really. why not?
#
# Stick this in RAILS_ROOT/config/initializers/connection_fix.rb (or somewhere similar)
#
# From:
#   http://coderrr.wordpress.com/2009/01/08/activerecord-threading-issues-and-resolutions/

module ActiveRecord::ConnectionAdapters
  class MysqlAdapter
    alias_method :execute_without_retry, :execute

    def execute(*args)
      retried = false
      begin
        execute_without_retry(*args)
      rescue ActiveRecord::StatementInvalid, Mysql::Error => e
        # Attempt to reconnect, then re-execute the query.
        if !retried && e.message =~ /server has gone away/i
          retried = true
          warn "Server timed out, retrying."
          reconnect!
          retry
        else
          raise e
        end
      end
    end
  end
end