On Wed, Jun 24, 2015 at 4:31 AM, Mikael Abrahamsson <[email protected]> wrote: > On Tue, 23 Jun 2015, Sebastian Moeller wrote: > >> As Dave said it would be nice see RRUL data from the same testbed. It >> would be so nice if flint had a way to send different sized TCP packets… (I >> guess this might be faked with MSS clamping in the router and relaying on >> path MTU discovery?) > > > What kind of tests should I run? I have rrul results now, both at the same > time as running iperf3. I set iperf3 to run with 10 parallel streams, > different MSS per test, and let it run for 30 seconds into the rrul test. So > in all the tests, iperf3 session stops running half way into the rrul test. > > I set sqm to 500M up and down on eth0, ECN up and down, and not to squash > DSCP in any direction. > > http://swm.pp.se/aqm/rrul-wrt1200ac-150624.pdf
From what I see here you are rarely, if ever, engaging fq_codel properly. Latencies are pretty high. In particular, I would suspect you are hitting offloads hard, and the current (fixed in linux 4.1) codel drop algorithm stops dropping below "maxpacket", which was meant in the ns2 code to be a MTU, but in the linux code ended up being a TSO sized (64k!) packet. tc -s qdisc show # will show the maxpacket. > Tell me if there is more information I can provide or tests to run. 0) I tend to have a script for everything... I can give you an example script in another email. 1) tc -s qdisc show dev whatever # will show actuall drop/mark statistics 2) Please run your flent tests with -x --disable-log -x collects more metadata, --disable-log disables the automatic log scaling which is so hard to discern on these plots. Use -t "title" to differentiate between variables under test. 3) I also tend to use flent's --remote-metadata=root@your_openwrtbox to get the stats on that box into the metadata. You have to add your local .ssh/id_rsa.pub key to your_openwrtbox:/etc/dropbear/authorized_keys file to do this. 4) With all that in hand, sticking up a tarball of the results makes for easy plotting of various other graphs, and using the flent-gui, you can combine results from each run easily, also. 5) try disabling offloads on all interfaces on the router (or running cake) My usual suite of tests is rrul, rrul_be, tcp_1up, tcp_1down, and tcp_2up_delay. and rtt_fair (if you have more than one target server available)... all without the iperf stuff.... Your mss changing idea is interesting, and I would like to do a mod to tcp_2up_delay to sort of match your iperf combination + flent to totally capture all data. 6) I am pretty interested as to what happens *without* sqm at the max forwarding rate with fq_codel engaged on all these tests. > > -- > Mikael Abrahamsson email: [email protected] > > _______________________________________________ > Cerowrt-devel mailing list > [email protected] > https://lists.bufferbloat.net/listinfo/cerowrt-devel > -- Dave Täht worldwide bufferbloat report: http://www.dslreports.com/speedtest/results/bufferbloat And: What will it take to vastly improve wifi for everyone? https://plus.google.com/u/0/explore/makewififast _______________________________________________ Cerowrt-devel mailing list [email protected] https://lists.bufferbloat.net/listinfo/cerowrt-devel
