<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"><meta http-equiv="Content-Type" content="text/html charset=utf-8"><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">We’ve measured timings like this on many 3GPP based systems in various countries.<div class=""><br class=""></div><div class="">It is an interaction between the radio link protocol, other parts of the 3GPP data path and way</div><div class="">in which such devices are integrated with the operating system (even in iOS), it is</div><div class="">not about the quantity of buffers but more the protocol interactions during times of stress on the</div><div class="">radio bearer and/or during handover.</div><div class=""><br class=""></div><div class="">There are protocol configuration options, different design objectives and operational management</div><div class="">mechanisms they _could_ use, but there is no incentive for the cellular operators to invest the</div><div class="">time and effort to investigate and resolve.</div><div class=""><br class=""></div><div class="">The same mindset that created these sort of performance artefacts is also driving changes in DSL </div><div class="">standards, so watch out for these sort of artefacts (again induced by things that you have no direct</div><div class="">control over) starting to occur in “high speed” DSL systems (such as VDSL) when conditions are less</div><div class="">than perfect.</div><div class=""><br class=""></div><div class="">Neil</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On 31 Jan 2017, at 20:42, Jim Gettys <<a href="mailto:jg@freedesktop.org" class="">jg@freedesktop.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><div class="gmail_extra"><br class="Apple-interchange-newline"><br class=""><div class="gmail_quote">On Tue, Jan 31, 2017 at 3:13 PM, Dave Taht<span class="Apple-converted-space"> </span><span dir="ltr" class=""><<a href="mailto:dave.taht@gmail.com" target="_blank" class="">dave.taht@gmail.com</a>></span><span class="Apple-converted-space"> </span>wrote:<br class=""><blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex;"><span class="">On Tue, Jan 31, 2017 at 12:02 PM, Aaron Wood <<a href="mailto:woody77@gmail.com" class="">woody77@gmail.com</a>> wrote:<br class="">> This is wifi tethering from my OSX laptop to my iPhone, right after the<br class="">> laptop tried to reconnect to the iphone after waking up.<br class="">><br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=0 ttl=56 time=42907.196 ms<br class=""><br class=""></span>Not even close for the record as we got something like 800 seconds out<br class="">of gogo-in-flight. But as for wifi + tethering, you "win", I guess.<br class=""></blockquote><div class=""><br class=""></div><div class=""><div class="gmail_default" style="font-size: small; display: inline;">I measured GoGo a couple years ago at about 740 seconds(!).</div></div><div class=""><div class="gmail_default" style="font-size: small; display: inline;"><br class=""></div></div><div class=""><div class="gmail_default" style="font-size: small; display: inline;">IIRC, we've seen some other cellular systems with bloat at >60 seconds.</div></div><div class=""><div class="gmail_default" style="font-size: small; display: inline;"><br class=""></div></div><div class="gmail_default" style="font-size: small;">I don't understand what I'm seeing at the moment on my Pixel XL on T-Mobile (upstream). I need to retake the data and post it along with the qdisc structure on current Android, for people to mull over.</div><div class="gmail_default" style="font-size: small;"> - Jim</div><div class="gmail_default" style="font-size: small;"></div><blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex;"><div class=""><div class="h5"><br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=1 ttl=56 time=41922.290 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=2 ttl=56 time=40971.714 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=3 ttl=56 time=39967.402 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=4 ttl=56 time=38964.115 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=5 ttl=56 time=37986.640 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=6 ttl=56 time=37026.309 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=7 ttl=56 time=36073.683 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=8 ttl=56 time=35075.141 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=17 ttl=56 time=26273.867 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=18 ttl=56 time=25268.726 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=19 ttl=56 time=24270.618 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=20 ttl=56 time=23269.550 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=21 ttl=56 time=22265.406 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=22 ttl=56 time=21264.648 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=23 ttl=56 time=20305.022 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=24 ttl=56 time=19316.740 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=26 ttl=56 time=17310.953 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=25 ttl=56 time=18316.163 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=27 ttl=56 time=16320.196 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=28 ttl=56 time=15409.592 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=29 ttl=56 time=14411.919 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=30 ttl=56 time=13505.362 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=31 ttl=56 time=12505.893 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=32 ttl=56 time=11502.744 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=33 ttl=56 time=10501.390 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=34 ttl=56 time=9560.551 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=35 ttl=56 time=8566.430 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=36 ttl=56 time=7570.286 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=37 ttl=56 time=6588.928 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=38 ttl=56 time=5643.342 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=39 ttl=56 time=4639.435 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=40 ttl=56 time=3722.169 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=41 ttl=56 time=2719.881 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=42 ttl=56 time=1806.913 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=43 ttl=56 time=1218.198 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=55 ttl=43 time=1030.052 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=56 ttl=43 time=638.601 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=57 ttl=43 time=216.295 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=58 ttl=43 time=200.674 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=59 ttl=43 time=797.261 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=60 ttl=43 time=992.238 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=61 ttl=43 time=1696.089 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=62 ttl=43 time=1139.896 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=63 ttl=43 time=588.823 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=64 ttl=43 time=663.070 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=65 ttl=43 time=782.507 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=66 ttl=43 time=426.705 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=67 ttl=43 time=220.192 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=68 ttl=43 time=228.405 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=69 ttl=43 time=130.555 ms<br class="">> 64 bytes from<span class="Apple-converted-space"> </span><a href="http://8.8.8.8/" rel="noreferrer" target="_blank" class="">8.8.8.8</a>: icmp_seq=70 ttl=43 time=210.779 ms<br class="">><br class="">> -Aaron<br class="">><br class=""></div></div>> ______________________________<wbr class="">_________________<br class="">> Bloat mailing list<br class="">><span class="Apple-converted-space"> </span><a href="mailto:Bloat@lists.bufferbloat.net" class="">Bloat@lists.bufferbloat.net</a><br class="">><span class="Apple-converted-space"> </span><a href="https://lists.bufferbloat.net/listinfo/bloat" rel="noreferrer" target="_blank" class="">https://lists.bufferbloat.net/<wbr class="">listinfo/bloat</a><br class="">><br class=""><span class="HOEnZb"><font color="#888888" class=""><br class=""><br class=""><br class="">--<br class="">Dave Täht<br class="">Let's go make home routers and wifi faster! With better software!<br class=""><a href="http://blog.cerowrt.org/" rel="noreferrer" target="_blank" class="">http://blog.cerowrt.org</a><br class="">______________________________<wbr class="">_________________<br class="">Bloat mailing list<br class=""><a href="mailto:Bloat@lists.bufferbloat.net" class="">Bloat@lists.bufferbloat.net</a><br class=""><a href="https://lists.bufferbloat.net/listinfo/bloat" rel="noreferrer" target="_blank" class="">https://lists.bufferbloat.net/<wbr class="">listinfo/bloat</a><br class=""></font></span></blockquote></div><br class=""></div></div><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">_______________________________________________</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">Bloat mailing list</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="mailto:Bloat@lists.bufferbloat.net" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">Bloat@lists.bufferbloat.net</a><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="https://lists.bufferbloat.net/listinfo/bloat" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">https://lists.bufferbloat.net/listinfo/bloat</a></div></blockquote></div><br class=""></div></body></html>