[c-nsp] GigE Max Speed

[Hank Nussbacher]

On Fri, 18 Jul 2008, Lincoln Dale wrote:

> 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 .. :)

Why not add something like:
hold-queue 1024 out
hold-queue 1024 in

-Hank