[c-nsp] GigE Max Speed

[Lincoln Dale]

Paul Stewart wrote:
> Hi there...
>
> One on our our 7606's we have a GigE link that is getting fairly "hot" with
> traffic....
>
> GigabitEthernet4/1 is up, line protocol is up (connected)
>   
..
>   Input queue: 0/2000/438/0 (size/max/drops/flushes); Total output drops:
> 98911
>   5 minute output rate 817892000 bits/sec, 133528 packets/sec
>   
...
>      406989787118 packets output, 241435931635384 bytes, 0 underruns
>
> I've ordered a new x-connect with the idea of running etherchannel... my
> real question is how much further can I push this link? There's no latency
> or issues that are evident yet but wanted to ask anyways....
>   
you're pushing it pretty hard already.  a 5 minute average of 817 Mbps 
would probably imply instantaneously pushing 1 Gbps.

more granular statistics (e.g. setting load-interval to 30 seconds) may 
show more dynamic nature than a 5 minute average, but i'd say getting 15 
or 30 second SNMP counters may show you hitting 1Gbps for periods of time.

latency would be a function of queuing & average queue length.
based on your statistics, you have 98K output queue drops (queue was 
full) based on 406 billion packets -- so it clearly isn't happening 
_too_ often ... yet .. :)


cheers,

lincoln.