The factor of 6 was just in reduction of overhead. Granted in the greater scheme of things the overall 4% is relatively insignificant, but there have been many times when doing multiple 10-100+GB transfers that I would have welcomed a 4% reduction of time spent twiddling thumbs!
-----Original Message----- From: Jakob Heitz (jheitz) [mailto:jhe...@cisco.com] Sent: Saturday, March 19, 2016 00:34 To: Tim McKee Cc: Dale W. Carder; nanog@nanog.org Subject: Re: Internet Exchanges supporting jumbo frames? You would hardly notice it. Helium is 4 times as heavy as hydrogen, but only marginally less buoyant. Header overhead: Ethernet=38 IPv4=20 TCP=20 Total=78 Protocol efficiency: 1500: 1500/1578 = 95% 9000: 9000/9078 = 99% That's 4% better for a TCP packet, not 600%. Thanks, Jakob. > On Mar 18, 2016, at 6:45 PM, Tim McKee <t...@baseworx.net> wrote: > > I would hazard a guess that reducing the packet header overhead *and* the > Ethernet interframe gap time by a factor of 6 could make enough of an > improvement to be quite noticeable when dealing with huge dataset transfers. > > Tim McKee > > -----Original Message----- > From: NANOG [mailto:nanog-boun...@nanog.org] On Behalf Of Jakob Heitz > (jheitz) > Sent: Friday, March 18, 2016 18:21 > To: Dale W. Carder > Cc: nanog@nanog.org > Subject: RE: Internet Exchanges supporting jumbo frames? > > Then it's mainly TCP slowstart that you're trying to improve? > > Thanks, > Jakob. > >> -----Original Message----- >> From: Dale W. Carder [mailto:dwcar...@wisc.edu] >> Sent: Friday, March 18, 2016 3:03 PM >> To: Jakob Heitz (jheitz) <jhe...@cisco.com> >> Cc: nanog@nanog.org >> Subject: Re: Internet Exchanges supporting jumbo frames? >> >> Thus spake Jakob Heitz (jheitz) (jhe...@cisco.com) on Fri, Mar 18, 2016 at >> 09:29:44PM +0000: >>> What's driving the desire for larger packets? >> >> In our little corner of the internet, it is to increase the >> performance of a low number of high-bdp flows which are typically dataset >> transfers. >> All of our non-commercial peers support 9k. >> >> Dale > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2015.0.6189 / Virus Database: 4542/11829 - Release Date: > 03/17/16 ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6189 / Virus Database: 4542/11841 - Release Date: 03/19/16
