[tsvwg] per-flow scheduling

Bob Briscoe <ietf@bobbriscoe.net> Wed, 19 June 2019 14:12 UTC

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To: "Holland, Jake" <jholland@akamai.com>
Cc: "ecn-sane@lists.bufferbloat.net" <ecn-sane@lists.bufferbloat.net>, tsvwg IETF list <tsvwg@ietf.org>
From: Bob Briscoe <ietf@bobbriscoe.net>
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Date: Wed, 19 Jun 2019 15:12:53 +0100
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Subject: [tsvwg] per-flow scheduling
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Jake, all,

You may not be aware of my long history of concern about how per-flow 
scheduling within endpoints and networks will limit the Internet in 
future. I find per-flow scheduling a violation of the e2e principle in 
such a profound way - the dynamic choice of the spacing between packets 
- that most people don't even associate it with the e2e principle.

I detected that you were talking about FQ in a way that might have 
assumed my concern with it was just about implementation complexity. If 
you (or anyone watching) is not aware of the architectural concerns with 
per-flow scheduling, I can enumerate them.

I originally started working on what became L4S to prove that it was 
possible to separate out reducing queuing delay from throughput 
scheduling. When Koen and I started working together on this, we 
discovered we had identical concerns on this.



Bob


-- 
________________________________________________________________
Bob Briscoe                               http://bobbriscoe.net/