Hi Dave, sugarland really took stability under load to a new level. My typical UDP flooding experiments failed to take the router down even though I opened the flood gates for a full hour (against qos; will repeat against simple-qos once time permits); not even a single report in dmesg on the router. Nice work. Thanks for all the hard work. (If time allows I will try to run a few more stability tests and will report noteworthy results back, if any should show up)
best sebastian On Sep 19, 2012, at 09:49 , Dave Taht wrote: > I am enjoying the thread on agile over here: http://esr.ibiblio.org/?p=4564 > > Trying to formalize some stuff that I do instinctively into language > more folk grok would be good. > > One of the better links to come from it was this one: > > http://blogs.valvesoftware.com/abrash/valve-how-i-got-here-what-its-like-and-what-im-doing-2/ > > This is something like what we've done with the bufferbloat effort - > find something worthwhile, start a project to do it. However steam has > a revenue model that we thus far lack. It does help to be making > something lots of people want, and I suppose the hard problem is > making people aware we have something they want. > > Speaking of that, the 3.6-rc6 kernel I was working on which has most > of the cerowrt stuff in it, but for x86 and ubuntu is here: > http://snapon.lab.bufferbloat.net/~cero1/deb/ > > and (in trying to lick the memory problems) I've been doing some > builds for the 32MB ram nanostation M5 and picostation 2HP, based on > the current cerowrt patch sets. With a single SSID I haven't been able > to crash the 2HP yet with a variety of traffic. It's easy to calculate > however how to crash nearly any access point with extra SSIDs > > if (Total spare ram - (4 wireless queues, 1000 packets = 2Mbytes > roughly for each = 8Mbytes) * SSIDS) < 0) > boom() > > This would be improvable with a multi hw queue fq_codel as each > hardware queue could share an overall fq_codel queue (factor of 4 > decrease), however, it seems to make more sense to have the queueing > in the mac layer below the SSID abstractions. > > What's currently in cerowrt is eric dumazet's suggestions to reduce > packet allocations under load. The above math was worse before - no > matter the packet size, it seemed as though 2k and 4k allocations > would be exausted. > > ... > > After I recover from the sprint required to get "sugarland" out the > door, I'd like to work on ways to do scrum and sprint-like things > (google hangouts?) to spread the knowledge and work around, and to > parallelize the effort more. > So much work remains. Truly addressing the wireless problem hasn't > even started. > > I have to admit that after doing something like 30 official releases > of cerowrt out the last 18 months, I'd > really like to hand over the reins to that to someone else. Worse is > after the openwrt unfreeze, new kernels will start to appear, and > while working with Linux 3.6 and later would be helpful, I'd rather > have stability for a while to work on higher layers of the stack, and > get analytical. Doing both "stable" maintainence and trying to move > forward on new kernels is a problem... > > Next up for me is working on qos-scripts, analytical models and tests, > and updating my test deployment to > this generation of code if all goes well. I just dumped a ton of raw > data into the deBloat repo, too. Also have a few patches for the linux > and openwrt mainlines to polish... > > On other fronts, I'm still working the basic funding angles and trying > to fix things with amazon. I was encouraged enough by your (thus far > failed) attempts at financial help to sink the time I did into > sugarland (sugar helped too, I think she needs a job title). If it > wasn't for the outpouring of your support, I'd have given up. Thx. I > sure hope sugarland is better than -10. > > There has been an upswing in corporate interest in the last few weeks, > I may have some news on that shortly. > > I had planned originally to get to barcelona for the wireless summit > and the linux conference. I may still make the second (issue is in > doubt, though). Is anyone besides jg going to this? > > http://www.wirelesssummit.org/ > > It's near the home of guifi.net which is one of the larger wireless > networks I've ever heard of. > > -- > Dave Täht > http://www.bufferbloat.net/projects/cerowrt/wiki - "3.3.8-26 is out > with fq_codel!" > _______________________________________________ > Cerowrt-devel mailing list > Cerowrt-devel@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cerowrt-devel _______________________________________________ Cerowrt-devel mailing list Cerowrt-devel@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/cerowrt-devel