On Mon, Oct 31, 2022 at 4:32 PM dan via LibreQoS <libreqos@lists.bufferbloat.net> wrote: > > preseems numbers ar -074 green, 75-124 yellow, 125-200 red, and they just > consolidate everything >200 to 200, basically so there's no 'terrible' color > lol.
I am sorry to hear those numbers are considered to be good. My numbers are based on human factors research, some of which are cited here: https://gettys.wordpress.com/2013/07/10/low-latency-requires-smart-queuing-traditional-aqm-is-not-enough/ > I think these numbers are reasonable for standard internet service these > days. for a 'default' value anyway. >100ms isn't bad service for most > people, and most wisps will have a LOT of traffic coming through with >100ms > from the far reaches of the internet. I'm puzzled, actually. Given the rise of CDNs I would expect most internet connections to the ISP to have far less than 60ms latency at this point. Google, is typically 2ms away from most fiber in the eu, for example. Very few transactions go to the far reaches of the planet anymore, but I do lack real world data on that. > > Maybe just reasonable defaults like preseem uses for integrated 'generic' > tracking, but then have a separate graph hitting some target services. ie, > try to get game servers on there, AWS, Cloudflare, Azure, Google cloud. Show > a radar graphic or similar. My thought for slices of the data (2nd tier support and CTO level) would be ISP infrastructure (aquamarine, less than 3ms) First hop infrastructure (blue, less than 8ms) ISP -> customer - 10-20ms (green) for wired, much worse for wifi customer to world - ideally, sub 50ms. I can certainly agree that the metaverse metrics are scary given the state of things you describe, but the 8ms figure is the bare minimum to have an acceptible experience in that virtual world. > > On Mon, Oct 31, 2022 at 3:57 PM Robert Chacón via LibreQoS > <libreqos@lists.bufferbloat.net> wrote: >> >> > I'd agree with color coding (when it exists - no rush, IMO) being >> > configurable. >> >> Thankfully it will be configurable, and easily, through the InfluxDB >> interface. >> Any operator will be able to click the Gear icon above the tables and set >> the thresholds to whatever is desired. >> I've set it to include both a standard table and "metaverse-ready" table >> based on Dave's threshold recommendations. >> >> Standard (Preseem like) >> >> green = < 75 ms >> yellow = < 100 ms >> red = > 100 ms >> >> Metaverse-Ready aquamarine <= 3ms >> blue = < 8ms >> green = < 20ms >> yellow = < 50ms >> orange = < 70ms >> red = > 70ms mordor-red = >100ms >> Are the defaults here reasonable at least? Should we change the Standard >> table thresholds a bit? Following exactly preseems current breakdown seems best for the "preseem" table. Calling it "standard", kind of requires actual standards. >> >> > Only adding 0.00155 ms to packet times is pretty good. >> >> Agreed! That's excellent. Great work on this so far it's looking like you're >> making tremendous progress. >> >> On Mon, Oct 31, 2022 at 3:20 PM Herbert Wolverson via LibreQoS >> <libreqos@lists.bufferbloat.net> wrote: >>> >>> I'd agree with color coding (when it exists - no rush, IMO) being >>> configurable. >>> >>> From the "how much delay are we adding" discussion earlier, I thought I'd >>> do a little bit of profiling of the BPF programs themselves. This is with >>> the latest round of performance updates >>> (https://github.com/thebracket/cpumap-pping/issues/2), so it's not >>> measuring anything in production. I simply added a call to get the clock at >>> the start, and again at the end - and log the difference. Measuring both >>> XDP and TC BPF programs. (Execution goes (packet arrives)->(XDP cpumap >>> sends it to the right CPU)->(egress)->(TC sends it to the right classifier, >>> on the correct CPU and measures RTT latency). This is adding about two >>> clock checks and a debug log entry to execution time, so measuring it is >>> slowing it down. >>> >>> The results are interesting, and mostly tell me to try a different >>> measurement system. I'm seeing a pretty wide variance. Hammering it with an >>> iperf session and a queue capped at 5 gbit/s: most of the TC timings were >>> 40 nanoseconds - not a packet that requires extra tracking, already in >>> cache, so proceed. When the TCP RTT tracker fired and recorded a >>> performance event, it peaked at 5,900 nanoseconds. So the tc xdp program >>> seems to be adding a worst-case of 0.0059 ms to packet times. The XDP side >>> of things is typically in the 300-400 nanosecond range, I saw a handful of >>> worst-case numbers in the 3400 nanosecond range. So the XDP side is adding >>> 0.00349 ms. So - assuming worst case (and keeping the overhead added by the >>> not-so-great monitoring), we're adding 0.0093 ms to packet transit time >>> with the BPF programs. >>> >>> With a much more sedate queue (ceiling 500 mbit/s), I saw much more >>> consistent numbers. The vast majority of XDP timings were in the 75-150 >>> nanosecond range, and TC was a consistent 50-55 nanoseconds when it didn't >>> have an update to perform - peaking very occasionally at 1500 nanoseconds. >>> Only adding 0.00155 ms to packet times is pretty good. >>> >>> It definitely performs best on long streams, probably because the previous >>> lookups are all in cache. This is also making me question the answer I >>> found to "how long does it take to read the clock?" I'd seen ballpark >>> estimates of 53 nanoseconds. Given that this reads the clock twice, that >>> can't be right. (I'm *really* not sure how to measure that one) >>> >>> Again - not a great test (I'll have to learn the perf system to do this >>> properly - which in turn opens up the potential for flame graphs and some >>> proper tracing). Interesting ballpark, though. >>> >>> On Mon, Oct 31, 2022 at 10:56 AM dan <danden...@gmail.com> wrote: >>>> >>>> >>>> >>>> On Sun, Oct 30, 2022 at 8:21 PM Dave Taht via LibreQoS >>>> <libreqos@lists.bufferbloat.net> wrote: >>>>> >>>>> How about the idea of "metaverse-ready" metrics, with one table that is >>>>> preseem-like and another that's >>>>> >>>>> blue = < 8ms >>>>> green = < 20ms >>>>> yellow = < 50ms >>>>> orange = < 70ms >>>>> red = > 70ms >>>> >>>> >>>> These need configurable. There are a lot of wisps that would have >>>> everything orange/red. We're considering anything under 100ms good on the >>>> rural plans. Also keep in mind that if you're tracking latence via pping >>>> etc, then you need some buffer in there for the internet at large. <70ms >>>> to Amazon is one thing, they're very well connected, but <70ms to most of >>>> the internet isn't probably very realistic and would make most charts look >>>> like poop. >>> >>> _______________________________________________ >>> LibreQoS mailing list >>> LibreQoS@lists.bufferbloat.net >>> https://lists.bufferbloat.net/listinfo/libreqos >> >> >> >> -- >> Robert Chacón >> CEO | JackRabbit Wireless LLC >> Dev | LibreQoS.io >> >> _______________________________________________ >> LibreQoS mailing list >> LibreQoS@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/libreqos > > _______________________________________________ > LibreQoS mailing list > LibreQoS@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/libreqos -- This song goes out to all the folk that thought Stadia would work: https://www.linkedin.com/posts/dtaht_the-mushroom-song-activity-6981366665607352320-FXtz Dave Täht CEO, TekLibre, LLC _______________________________________________ LibreQoS mailing list LibreQoS@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/libreqos
