mark_dead (MemCache::Server)

    # File lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 1024
        def mark_dead(error)
          @sock.close if @sock && !@sock.closed?
          @sock   = nil
          @retry  = Time.now + RETRY_DELAY

          reason = "#{error.class.name}: #{error.message}"
          @status = sprintf "%s:%s DEAD (%s), will retry at %s", @host, @port, reason, @retry
          @logger.info { @status } if @logger
        end