jumbo frames

Fri Apr 27 15:44:30 UTC 2001

I am not an EE but maybe if you rephrased the question as

Which is greater, the cpu cycles to assemble/dissemble jumbo frames or the
additional cycles/bandwidth of more numerous ACK packets?

Then again, I may be way out of my depth here.

-Al

-----Original Message-----
From: Kurt Kayser [mailto:kurt at noris.de]
Sent: Friday, April 27, 2001 8:07 AM
To: Tony Hain
Cc: Roeland Meyer; John Fraizer; Paul Lantinga; nanog at merit.edu
Subject: Re: jumbo frames

Hi,

Isn't it a lot more cpu-intensive to 'collect' some 1500-byte frames
into some larger bucket, reassemble it into a jumbo-frame when the next
box has to chop it in order to send it out on a Sonet/PPP/etc interface
which 
might have a smaller MTU again?

Doesn't make too much sense to me. I guess that was Tony's aim as well..

Kurt

> Roeland you are talking about jumbo frames from the end system lan, while
> John is talking about only using the jumbo frames between the routers. My
> point was that in John's environment the packets will all be 1500 since
the
> packets are restricted to that size just to get to the router with the GE
> interface. I understand that there are perf gains as long as the entire
path
> supports the larger packets, but I don't understand the claim that having
a
> bigger pipe in the middle helps.
> 
> Tony
> 
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