Dnia Monday 10 of March 2008, Gerrit Renker napisał: > Now I have a question: adding 1 ms delay at the interface avoided the > hang-up, but what do you mean by "long enough"? Is this 60 seconds? > I tested it for something like 100 seconds and didn't encounter any problems. > But since the average RTT is 48 microseconds in the `outfile', I am > assuming that the outfile was produced when the delay was not added to > the interface? > Yes, that's what I thought you asked me for... > There is a long-standing problem (at least 1 year) with regard to CCID-3 > over high-speed networks (and lo interface is in fact a high-speed > interface): high link speeds are outside the control region of CCID-3. > > The peak limit of controllable speed is about 12 Mbps. Everything higher > that will cause problems. I have not tested, but you may be able to > also silence this behaviour by using a netem token-bucket filter with > e.g. a maximum bitrate of <= 10 Mbps. > I somehow doubt it because setting up tbf with limit greater than the actual traffic should have no influence at all. But let's check it... sudo tc qdisc add dev lo root handle 1:0 tbf rate 30kbit burst 30kbit latency 500ms Still the speed drops down to 1 packet per 64 seconds. > So I think the least thing we need to do is put a warning into the DCCP > Wiki that people should add interface delay when using CCID-3 for > testing over loopback. Maybe CCID-3 could somehow disable itself when it detects it is not necessary? -- Regards, Tomasz Grobelny -- To unsubscribe from this list: send the line "unsubscribe dccp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
