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Re: [tcpm] Tuning TCP parameters for the 21st century

Jerry Chu <hkchu@google.com> Thu, 16 July 2009 18:24 UTC

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Date: Thu, 16 Jul 2009 11:24:53 -0700
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From: Jerry Chu <hkchu@google.com>
To: David Malone <David.Malone@nuim.ie>
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Subject: Re: [tcpm] Tuning TCP parameters for the 21st century
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On Thu, Jul 16, 2009 at 2:09 AM, David Malone<David.Malone@nuim.ie> wrote:
>> We have seen SYN-ACK retransmission rates upto a few percentage points to
>> some of our servers.
>
> Note, that I've seen Google reported to have unusually SYN-ACK
> retransmission rates in this paper:
>
>        http://www.springerlink.com/content/t033171209815745/
>
> Are Google already doing something unusual with their SYN-ACK
> retransmissions?

I can't access the above link so don't know what the unusual SYN-ACK
retransmission rate is. We are experiementing with using RTT history
on a handful of servers as mentioned before. Otherwise our SYN-ACK
retransmit rate seems pretty much on par with the general pkt retransmit
rate, and can go up to a few percentage in regions like India, China...

Jerry

>
>        David.
>

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