Re: [tcpm] TCP tuning

Michael Welzl <michawe@ifi.uio.no> Wed, 03 February 2010 14:41 UTC

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From: Michael Welzl <michawe@ifi.uio.no>
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Subject: Re: [tcpm] TCP tuning
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Hi all,

(sorry if this is a bit off topic, as the mentioned presentation is  
mainly
about using a larger initial window)

In the context of the discussion that Jerry brought up on parameter  
tuning,
one question that was raised was the initial RTO during the SYN - SYN/ 
ACK
exchange. I understand that we can't recommend to resend SYN's more
aggressively because this might cause a server to be overloaded with  
SYN's,
but why do we have to wait extremely long until we resend SYN/ACKs?

Back then, when I asked, I got no answer. Both Jerry and I pointed
to our measurement results which show that the effect is nonneglible.

So I'll use this chance to ask again  :-)

Cheers,
Michael


On Feb 3, 2010, at 3:28 PM, Lars Eggert wrote:

> Hi,
>
> Jerry Chu has recently started the discussion on whether we need to  
> think about tweaking TCP for the "modern Internet." Just came across  
> another presentation from (AFAICT) another corner of Google that  
> makes similar arguments.
>
> FYI: http://sites.google.com/a/chromium.org/dev/spdy/An_Argument_For_Changing_TCP_Slow_Start.pdf
>
> This topic seems to be gaining momentum, and the WG should take some  
> time considering if there is work here for it.
>
> Lars_______________________________________________
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