prepopulate

# File activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb, line 776
      def prepopulate
        need_new_connections = nil

        synchronize do
          return if self.discarded?

          # We don't want to start prepopulating until we know the pool is wanted,
          # so we can avoid maintaining full pools in one-off scripts etc.
          return unless @activated

          need_new_connections = @connections.size < @min_connections
        end

        if need_new_connections
          while new_conn = try_to_checkout_new_connection { @connections.size < @min_connections }
            new_conn.allow_preconnect = true
            checkin(new_conn)
          end
        end
      end