10GE TOR port buffers (was Re: 10G switch recommendaton)

Łukasz Bromirski lukasz at bromirski.net
Sat Jan 28 02:32:17 UTC 2012

On 2012-01-28 01:00, Joel jaeggli wrote:

>> C NSP has been full with threads about appalling microburst
>> performance of the 6500 for years..
> And people who care have been using something other than a c6500 for
> years. it's a 15 year old architecture, and it's had a pretty good run,
> but it's 2012.
> An ex8200 has 512MB per port on non-oversuscribed 10Gig ports and 42MB
> per port on 1Gig ports. that's a lot of ram.

6500 has up to 256MB for non-oversubscribed 10GE ports. People
complaining about microburst tend to use the cheapest 6704 linecard,
and 'microbursts' are a problem seen across most of the products that
don't even try to have a 1/12th of a 6500 history.

Everyone has it's own problems, and as people already said, not
understanding the way properly sized buffers influence the way TCP
traffic behaves can do more harm than good.

"There's no sense in being precise when |               Łukasz Bromirski
  you don't know what you're talking     |      jid:lbromirski at jabber.org
  about."               John von Neumann |    http://lukasz.bromirski.net

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