[c-nsp] Outbound drops on ME-3600X-24FS-M

[Abel Alejandro]

Hello,

I have a ME-3600X-24FS-M with a 10GE interface facing an LTE core network and a 1GE interface to a remote node. 
The client wants to achieve 50Mbps on a single tcp session with an RTT of 50ms, so the BDP is about 300KB, however the congestion
window seems to be stuck at around 44KB due to packet drops due to the microbursts.

The offending interface appears to be:

GigabitEthernet0/23 is up, line protocol is up (connected)
 Hardware is Gigabit Ethernet, address is 24b6.574b.5297 (bia
24b6.574b.5297)
 Description:
 MTU 1610 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
    reliability 255/255, txload 1/255, rxload 1/255
 Encapsulation ARPA, loopback not set
 Keepalive not set
 Full-duplex, 1000Mb/s, media type is LX
 input flow-control is off, output flow-control is unsupported
 ARP type: ARPA, ARP Timeout 04:00:00
 Last input never, output never, output hang never
 Last clearing of "show interface" counters 05:10:14
 Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops:
1815
 Queueing strategy: fifo
 Output queue: 0/2512 (size/max)
 30 second input rate 1000 bits/sec, 1 packets/sec
 30 second output rate 48000 bits/sec, 11 packets/sec
    31938 packets input, 2874462 bytes, 0 no buffer
    Received 31938 broadcasts (31938 multicasts)
    0 runts, 0 giants, 0 throttles
    0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
    0 watchdog, 31938 multicast, 0 pause input
    0 input packets with dribble condition detected
    13997301 packets output, 19484128487 bytes, 0 underruns
    0 output errors, 0 collisions, 0 interface resets
    0 unknown protocol drops
    0 babbles, 0 late collision, 0 deferred
    0 lost carrier, 0 no carrier, 0 pause output
    0 output buffer failures, 0 output buffers swapped out

We increased the output queue but still getting drops, any other tips?

Thanks,
Abel.