nanog mailing list archives
Re: 10GE TOR port buffers (was Re: 10G switch recommendaton)
From: Masataka Ohta <mohta () necom830 hpcl titech ac jp>
Date: Sat, 28 Jan 2012 21:06:18 +0900
Saku Ytti wrote:
No, you're not crazy. If your core is higher rate than your customer, then you need at minimum serialization delay difference of buffering. If core is 10G and access 100M, you need buffer for minimum of 100 packets, to handle the single 10G incoming, without any extra buffering.
The required amount of memory is merely 150KB.
Now if you add QoS on top of this, you probably need 100 per each class you are going to support.
If you have 10 classes, it is still 1.5MB.
And if switch does support QoS but operator configures only BE, and operator does not limit BE queue size, operator will see buffer bloat,
1.5MB @ 10Gbps is only 1.2ms, which is not buffer bloat. Masataka Ohta
Current thread:
- Re: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)), (continued)
- Re: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) Leo Bicknell (Jan 27)
- RE: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) George Bonser (Jan 27)
- Re: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) Jared Mauch (Jan 29)
- RE: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) George Bonser (Jan 29)
- RE: pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) George Bonser (Jan 29)
- BDP discussion pointers: was: Re pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) Jim Gettys (Jan 28)
- Re: BDP discussion pointers: was: Re pontification bloat (was 10GE TOR port buffers (was Re: 10G switch recommendaton)) Jim Gettys (Jan 28)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Leo Bicknell (Jan 27)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Ćukasz Bromirski (Jan 27)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Saku Ytti (Jan 28)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Masataka Ohta (Jan 28)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Saku Ytti (Jan 28)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Masataka Ohta (Jan 28)
- Re: 10GE TOR port buffers (was Re: 10G switch recommendaton) Saku Ytti (Jan 28)