On Mon, 2016-06-13 at 22:45 +0200, Daniel Metz wrote: > This patch adjusts Linux RTO calculation to be RFC6298 Standard > compliant. MinRTO is no longer added to the computed RTO, RTO damping > and overestimation are decreased. > > In RFC 6298 Standard TCP Retransmission Timeout (RTO) calculation the > calculated RTO is rounded up to the Minimum RTO (MinRTO), if it is > less. The Linux implementation as a discrepancy to the Standard > basically adds the defined MinRTO to the calculated RTO. When > comparing both approaches, the Linux calculation seems to perform > worse for sender limited TCP flows like Telnet, SSH or constant bit > rate encoded transmissions, especially for Round Trip Times (RTT) of > 50ms to 800ms. > > Compared to the Linux implementation the RFC 6298 proposed RTO > calculation performs better and more precise in adapting to current > network characteristics. Extensive measurements for bulk data did not > show a negative impact of the adjusted calculation. > > Exemplary performance comparison for sender-limited-flows: > > - Rate: 10Mbit/s > - Delay: 200ms, Delay Variation: 10ms > - Time between each scheduled segment: 1s > - Amount Data Segments: 300 > - Mean of 11 runs > > Mean Response Waiting Time [milliseconds] > > PER [%] | 0.5 1 1.5 2 3 5 7 10 > --------+------------------------------------------------------- > old | 206.4 208.6 218.0 218.6 227.2 249.3 274.7 308.2 > new | 203.9 206.0 207.0 209.9 217.3 225.6 238.7 259.1 > > > Detailed Analysis: > > https://docs.google.com/document/d/1pKmPfnQb6fDK4qpiNVkN8cQyGE4wYDZukcuZfR-BnnM/ > > > Signed-off-by: Hagen Paul Pfeifer <ha...@jauu.net> > Signed-off-by: Daniel Metz <dm...@mytum.de> > Cc: Eric Dumazet <eduma...@google.com> > Cc: Yuchung Cheng <ych...@google.com> > Cc: Neal Cardwell <ncardw...@google.com> > --- > > We removed outdated comments in the code, though more cleanup may required. >
It seems you left mdev_max_us ?
