[Bloat] TCP BBR paper is now generally available

Steinar H. Gunderson sgunderson at bigfoot.com
Sat Dec 3 14:13:53 EST 2016

On Sat, Dec 03, 2016 at 08:03:50AM -0500, Neal Cardwell wrote:
> Thanks for the report, Steinar. This is the first report we've had
> like this, but it would be interesting to find out what's going on.
> Even if you don't have time to apply the patches Eric mentions, it
> would be hugely useful if the next time you have a slow transfer like
> that you could post a link to a tcpdump packet capture (headers only
> is best, say -s 120). Ideally the trace would capture a whole
> connection, so we can see the wscale on the SYN exchange.

I tried reproducing it now. I can't get as far down as 50 Mbit/sec,
but it stopped around 100 Mbit/sec, still without any clear bottlenecks.
cubic was just as bad, though.

I've taken two tcpdumps as requested; I can't reboot this server easily
right now, unfortunately. They are:

  http://storage.sesse.net/bbr.pcap -- ssh+tar+gnupg
  http://storage.sesse.net/bbr2.pcap -- wget between same hosts

/* Steinar */
Homepage: https://www.sesse.net/

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