At the last uknof meeting I had two questioners ask me for data on ADSL vs fq_codel and various rate shapers at the tail end of my talk:
http://www.youtube.com/watch?v=quAaZKBHvs8 Until recently the cable industry was paying the bills, not the adsl industry, and although I encouraged the questioners to do some of their own testing on their networks, I alluded to some puzzlement over the results we'd got with some preliminary testing with the ADSL devices we were able to open. We spent some more time poking into ADSL stuff recently and it turned out the Linux "tc" rate shaping mechanism for linklayer atm and related framing things like PPPoe has been broken in Linux for quite some time. Various fixes have been discussed, but there is no one working the problem directly, presently. The email thread discussing the problem(s) is here: https://lists.bufferbloat.net/pipermail/bloat/2013-May/001540.html And the bug turned out to be even deeper and older than we thought. This possibly explains a lot of the anomalies we've seen so far (but by no means all! waay too many binary blobs in dsl!) with rate shaping with hfsc/htb + fq_codel, and perhaps, also, some of the ones you've seen using your existing shapers. Whenever and however a fix or set of fixes arrives we'll go back to looking into it. -- Dave Täht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html
