On Tue, Apr 21, 2015 at 3:13 PM, jb wrote: > Today I've switched it back to large receive window max. > > The customer base is everything from GPRS to gigabit. But I know from > experience that if a test doesn't flatten someones gigabit connection they > will immediately assume "oh congested servers, insufficient capacity" and > the early adopters of fiber to the home and faster cable products are the > most visible in tech forums and so on. > > It would be interesting to set one or a few servers with a small receive > window, take them from the pool, and allow an option to select those, > otherwise they would not participate in any default run. Then as you point > out, the test can suggest trying those as an option for results with > chaotic upload speeds and probable bloat. The person would notice the > beauty of the more intimate connection between their kernel and a server, > and work harder to eliminate the problematic equipment. Or. They'd stop > telling me the test was bugged. > Well, the sawtooth pattern that's the classic sign of bufferbloat should be readily detectable, especially if the pings during the test climb in a similar fashion. And from the two sets of numbers, it should be possible to put a guess on how overbuffered the uplink is. Then when the test completes, an analysis that flags to the user that they have a bufferbloat issue might continue to shed light on this. Attached is results from my location which shows a couple hundred ms of bloat. While my results didn't have congestion collapse, they do clearly have a bunch of bloat. That amount of bloat should be easy to spot in an analysis of the results, and a recommendation to the user that they may want to look into fixing that if they use their link at the limit with VOIP or gaming. I just wish we had a really good un-bloated retail option to recommend. -Aaron