'send notification mail with some additional useful info'

def _send_report(self, rcpts, subject):

    stats = self.crawler.stats
    s = ('Memory    usage    at    engine    startup    :    %dM\r\n' % ((stats.get_value('memusage/startup') / 1024) / 1024))
    s += ('Maximum    memory    usage                                            :    %dM\r\n' % ((stats.get_value('memusage/max') / 1024) / 1024))
    s += ('Current    memory    usage                                            :    %dM\r\n' % ((self.get_virtual_size() / 1024) / 1024))
    s += 'ENGINE    STATUS    -------------------------------------------------------    \r\n'
    s += '\r\n'
    s += pformat(get_engine_status(self.crawler.engine))
    s += '\r\n'
    self.mail.send(rcpts, subject, s)
