code: def _configDevRequests(self, namestr, titlestr, devlist):
          
          name = 'diskio_%s_requests' % namestr
          if self.graphEnabled(name):
              graph = MuninGraph('Disk I/O - %s - Requests' % titlestr, self._category,
                  info='Disk I/O - %s Throughput, Read / write requests per second.' 
                       % titlestr,
                  args='--base 1000 --lower-limit 0',
                  vlabel='reqs/sec read (-) / write (+)', printf='%6.1lf',
                  autoFixNames = True)
              for dev in devlist:
                  graph.addField(dev + '_read',
                                 fixLabel(dev, maxLabelLenGraphDual, 
                                          repl = '..', truncend=False,
                                          delim = self._labelDelim.get(namestr)), 
                                 draw='LINE2', type='DERIVE', min=0, graph=False)
                  graph.addField(dev + '_write',
                                 fixLabel(dev, maxLabelLenGraphDual, 
                                          repl = '..', truncend=False,
                                          delim = self._labelDelim.get(namestr)),
                                 draw='LINE2', type='DERIVE', min=0, 
                                 negative=(dev + '_read'),info=dev)
              self.appendGraph(name, graph)
docs: Generate configuration for I/O Request stats.
          
          @param namestr:  Field name component indicating device type.
          @param titlestr: Title component indicating device type.
          @param devlist:  List of devices.