Re: [Lsr] Dynamic flow control for flooding

henk.ietf@xs4all.nl Wed, 24 July 2019 12:34 UTC

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Date: Wed, 24 Jul 2019 14:34:14 +0200
From: henk.ietf@xs4all.nl
To: "Les Ginsberg (ginsberg)" <ginsberg@cisco.com>
Cc: stephane.litkowski@orange.com, Tony Li <tony.li@tony.li>, lsr@ietf.org
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Subject: Re: [Lsr] Dynamic flow control for flooding
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Hello Les,

Les Ginsberg (ginsberg) schreef op 2019-07-24 07:17:
> 
> There is something to be said for simply “flooding fast” and not
> worrying about flow control at all (regardless of whether TX or RX
> mechanisms would be used). Some packets would be dropped, but
> retransmission timers will insure that the flooding eventually
> succeeds and retransmit timers are long (5 seconds by default). (I am
> not the only one mentioning this BTW…)

Why do we have initial waits and exponential backoffs for LSP-generation
and SPF-computations ? Why not react immediately ? Why not react 
constantly ?

We have a lot of bandwidth and cpu-power now. Isn't simple always better
than "overly complex stuff" like exponential backoffs ? If you have more
cpu-power, more memory and more bandwidth, why invent new algorithms ?

henk.


I hope it is clear to everyone that these are not serious questions. I'm 
just
saying: "sometimes fast is slow". I am sure that if we ask the "old 
guys", they
can come up with many stories how these problems are sometimes 
counter-intuitive.
And how networks have melted because "fast is slow". I could tell at 
least 2
of those stories myself.