[Bloat] [Codel] The challenge

[Eric Dumazet]

On Thu, 2012-05-10 at 02:08 +0200, Steinar H. Gunderson wrote:
> On Thu, May 10, 2012 at 01:58:39AM +0200, Eric Dumazet wrote:
> > One solution is at the producer level (TCP stack of the sender in this
> > case) to properly pace the transmits in MSS units given the RTT and
> > cwnd, supposedly done with TCP Hybla.
> 
> FWIW, I gave Hybla a quick test (echo hybla > /proc/sys/net/ipv4/tcp_congestion_control
> and then start a VLC server; Linux 3.3.4 on both sides), and it doesn't pace
> for me. It happily sends packets at what appears to be line speed, even to a
> host ~100ms away on a much slower line.

You should carefuly read http://hybla.deis.unibo.it/

Linux implementation

Starting from kernel 2.6.13 Hybla has been included in the official
Linux kernel. However, this implementation, based on the "module" Linux
technology, does not include the last two Hybla components: Hoe's
channel bandwidth estimate and packet spacing. Their addition is
mandatory to fully benefit from Hybla performance improvement. To this
end, it is enough to patch the official kernel with the MultiTCP
package, downloadable from the downloads section.