Date: Wed, 20 Apr 2016 06:07:28 +0000 From: Rasool Al-Saadi <ralsaadi@swin.edu.au> To: Don Lewis <truckman@FreeBSD.org> Cc: "freebsd-ipfw@FreeBSD.org" <freebsd-ipfw@FreeBSD.org> Subject: RE: Dummynet AQM v0.1- CoDel and FQ-CoDel for FreeBSD's ipfw/dummynet Message-ID: <6545444AE21C2749939E637E56594CEA3C20AEFC@gsp-ex02.ds.swin.edu.au> In-Reply-To: <201603100828.u2A8Smbt013642@gw.catspoiler.org> References: <6545444AE21C2749939E637E56594CEA3C187192@gsp-ex02.ds.swin.edu.au> <201603100828.u2A8Smbt013642@gw.catspoiler.org>
next in thread | previous in thread | raw e-mail | index | archive | help
> -----Original Message----- > From: Don Lewis [mailto:truckman@FreeBSD.org] > Sent: Thursday, March 10, 2016 7:29 PM > To: Rasool Al-Saadi <ralsaadi@swin.edu.au> > Cc: aqm@ietf.org; freebsd-net@FreeBSD.org; freebsd-ipfw@FreeBSD.org; > Grenville Armitage <garmitage@swin.edu.au> > Subject: Re: Dummynet AQM v0.1- CoDel and FQ-CoDel for FreeBSD's > ipfw/dummynet >=20 > On 26 Feb, Rasool Al-Saadi wrote: > > Dear all, > > > > I would like to announce that we (myself and Grenville Armitage) releas= ed > Dummynet AQM v0.1, which is an independent implementation of CoDel and > FQ-CoDel for FreeBSD's ipfw/dummynet framework, based on the IETF > CoDel [1] and FQ-CoDel [2] Internet-Drafts. > > We prepared patches for FreeBSD11-CURRENT-r295345 and FreeBSD 10.x- > RELEASE (10.0, 10.1, 10.2), and a technical report of our implementation= . > > > > Patches and documentation can be found in: > > http://caia.swin.edu.au/freebsd/aqm > > > > Technical report: > > http://caia.swin.edu.au/reports/160226A/CAIA-TR-160226A.pdf >=20 > I've got some results with running this on my firewall in an attempt to t= ame a > severe bufferbloat problem on my ADSL connection to the outside world. >=20 > The raw speed numbers reported by my ADSL modem are 6016 Kb/s > downstream and 768 Kb/s upstream. I set my MTU to 1492 to avoid > fragmentation from PPPoE overhead. >=20 > Using <http://www.dslreports.com/speedtest>; with things unthrottled, I > observe about 5050 Kb/s downstream and 648Kb/s upstream, with a > bufferbloat rating of F. >=20 > I configured the system to use FQ-CoDel, with separate pipes for each > direction. Because of the slow upstream speed, I increased the target va= lue > for the upstream direction to 25 ms since a maximum size packet will requ= ire > about 20 ms to send. I also set the > net.inet.tcp.experimental.initcwnd10 sysctl value to 0. The latter seeme= d to > help a lot. With this feature enabled, the initial packet blast at the s= tart of > the upload caused a large initial latency spike, and the initial transfer= rate > ended up being very slow and it took a long time to ramp up to its maximu= m > sustained value. >=20 > My current dummynet pipe bandwidth settings are 4800 Kb/s downstream > and > 615 Kb/s upstream. The speedtest results for these settings are about 46= 00 > Kb/s downstream and about 600 Kb/s upstream. I'm somewhat > disappointed in the bandwith loss, but my bufferbloat rating has improved= to > mostly A's with some B's. >=20 > I do still see a large increase in latency at the start of transfers, and= then it > oscillates for a while before settling down at a reasonable value for the > remainder of the transfer. I suspect this is to be expected. >=20 > It would be nice if the implementation was able to account for the PPPOE > and ATM framing overhead like the Linux implementation does. I think tha= t > would help performance when there is a mix of packet sizes. Dave T=E4ht suggests you to try a "quantum 300" for your 600kbit uplink. BTW, if you interested try our FQ-PIE implementation in Dummynet AQM v0.2 i= n your configuration. Regards, Rasool
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?6545444AE21C2749939E637E56594CEA3C20AEFC>