PPP multilink help

Rodney Dunn rodunn at cisco.com
Mon May 11 22:07:48 CDT 2009

It could very well be microburst in the flow creating congestion
as seen in the default class:

>   Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 252140

>   30 second output rate 1795000 bits/sec, 243 packets/sec
>     Class-map: class-default (match-any)
>       275000011 packets, 120951145536 bytes
>       30 second offered rate 1494000 bps, drop rate 0 bps
>       Match: any
>       Queueing
>       queue limit 64 packets
>       (queue depth/total drops/no-buffer drops/flowdrops) 0/251092/0/251092
>       (pkts output/bytes output) 276085337/122442704318
>       Fair-queue: per-flow queue limit 16

Which matches mostly to the default class. I don't recall if the per flow
queue limit kicks in without congestion or not.

You could try a few things:

a) remove WFQ in the default class
b) add a BW statement to it to allocate a dedicated amount
c) implement WRED in the class
d) remove WFQ in the default class

to see if one of those improves it.

btw, the overhead I was referring to was the additional MLPPP overhead
to each packet which reduces effective throughput.


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