This article describes the issue of the output of 'show interfaces queue IFD' being inaccurate.
The output of show interface queue IFD is not accurate. The example below, is a single IFL sending 350MB of data. The total trasmit bps rate is not accurate.
{MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 99090321 74965 pps Bytes : 116825042148 599723992 bps Transmitted: Packets : 46863385 43729 pps Bytes : 52741156948 349832520 bps <=== ok Tail-dropped packets : 29921244 1159 pps RED-dropped packets : 22305692 30076 pps Low : 22305692 30076 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22305692000 240612488 bps Low : 22305692000 240612488 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 99544823 101451 pps Bytes : 117279544148 811610712 bps Transmitted: Packets : 47128493 59175 pps Bytes : 53006264948 473407136 bps <=== ? Tail-dropped packets : 29928498 1619 pps RED-dropped packets : 22487832 40656 pps Low : 22487832 40656 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22487832000 325250000 bps Low : 22487832000 325250000 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 99696324 44822 pps Bytes : 117431045148 358582248 bps Transmitted: Packets : 47216884 26151 pps Bytes : 53094655948 209209464 bps <=== ? Tail-dropped packets : 29930747 665 pps RED-dropped packets : 22548693 18006 pps Low : 22548693 18006 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22548693000 144049704 bps Low : 22548693000 144049704 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 99999325 123171 pps Bytes : 117734046148 985369104 bps Transmitted: Packets : 47393594 71833 pps Bytes : 53271365948 574666664 bps Tail-dropped packets : 29935437 1906 pps RED-dropped packets : 22670294 49431 pps Low : 22670294 49431 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22670294000 395450400 bps Low : 22670294000 395450400 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 99999325 123171 pps Bytes : 117734046148 985369104 bps Transmitted: Packets : 47393594 71833 pps Bytes : 53271365948 574666664 bps Tail-dropped packets : 29935437 1906 pps RED-dropped packets : 22670294 49431 pps Low : 22670294 49431 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22670294000 395450400 bps Low : 22670294000 395450400 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9 egress forwarding-class be Physical interface: ge-10/0/9, Enabled, Physical link is Up Interface index: 240, SNMP ifIndex: 270 Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 100150825 45978 pps Bytes : 117885546148 367830040 bps Transmitted: Packets : 47481983 26825 pps Bytes : 53359754948 214601512 bps Tail-dropped packets : 29937781 711 pps RED-dropped packets : 22731061 18442 pps Low : 22731061 18442 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 22731061000 147537480 bps Low : 22731061000 147537480 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9.1000 egress forwarding-class be Logical interface ge-10/0/9.1000 (Index 109) (SNMP ifIndex 1563) Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 57519820 74998 pps Bytes : 57519799408 600003952 bps Transmitted: Packets : 33556220 43755 pps Bytes : 33556199408 350047520 bps Tail-dropped packets : 889562 1141 pps RED-dropped packets : 23074038 30102 pps Low : 23074038 30102 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 23074038000 240823760 bps Low : 23074038000 240823760 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9.1000 egress forwarding-class be Logical interface ge-10/0/9.1000 (Index 109) (SNMP ifIndex 1563) Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 57603759 74943 pps Bytes : 57603738408 599564280 bps Transmitted: Packets : 33605156 43692 pps Bytes : 33605135408 349542856 bps Tail-dropped packets : 890804 1108 pps RED-dropped packets : 23107799 30143 pps Low : 23107799 30143 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 23107799000 241150000 bps Low : 23107799000 241150000 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit] user@router# run show interfaces queue ge-10/0/9.1000 egress forwarding-class be Logical interface ge-10/0/9.1000 (Index 109) (SNMP ifIndex 1563) Forwarding classes: 16 supported, 8 in use Egress queues: 8 supported, 8 in use Queue: 0, Forwarding classes: be Queued: Packets : 57603759 74943 pps Bytes : 57603738408 599564280 bps Transmitted: Packets : 33605156 43692 pps Bytes : 33605135408 349542856 bps Tail-dropped packets : 890804 1108 pps RED-dropped packets : 23107799 30143 pps Low : 23107799 30143 pps Medium-low : 0 0 pps Medium-high : 0 0 pps High : 0 0 pps RED-dropped bytes : 23107799000 241150000 bps Low : 23107799000 241150000 bps Medium-low : 0 0 bps Medium-high : 0 0 bps High : 0 0 bps {MASTER}[edit]
Please wait for about 10 seconds between successive show interface commands. When the per-unit or hierarchical schedulers are configured, the software sums up the stats of the child nodes and this is not often enough for the stats to be accurate.
2020-02-19: minor non-technical updates.