I'm not a big fan of adding strings together like this. I think sprintf formatting looks nicer, and is much easier to read:

     return 'time -p java -Dblueflood.config=/opt/ele-conf/bf-0.conf -cp /opt/blueflood/blueflood.jar
            com.rackspacecloud.blueflood.ops.GetPoints -tenantId %s -metric %s' % (tenant_id, metric)