>> > > If that device behaves badly in router mode by blocking just all
>> > > icmp traffic instead of only icmp-echo-req, this is a good idea.
>> > > You may want to bug AT&T about this problem then. It should really
>> > > not block related icmp traffic.
>> >
>> >
>> > Hi Kai, yesterday I switched my Gentoo router over to handling PPPoE
>> > and pings seem to be working properly now.  The AT&T device is now
>> > functioning as a modem only and passing everything through.  Today
>> > I'll find out if it helps with TCP Queuing and (supposedly) related
>> > http response slowdowns.
>> You may want to set the default congestion control to fq-codel (it's
>> in the kernel) if you're using DSL links. This may help your problem a
>> little bit. It is most effective if you deploy traffic shaping at the
>> same time. There was once something like wondershaper. Trick is to get
>> the TCP queuing back inside your router (that is where you deployed
>> pppoe) as otherwise packets will queue up in the modem (dsl modems use
>> huge queues by default). This works by lowering the uplink bandwith to
>> 80-90% of measured maximum upload (the excess bandwidth is for short
>> bursts of traffic). Traffic shaping now re-orders the packets. It
>> should send ACK and small packets first. This should solve your
>> queuing problem.
>> Between each step check dslreports.com for bufferbloat. I'm guessing
>> it is currently way above 1000 ms while it should stay below 20-50 ms
>> for dsl.
>> The fq-codel congestion control fights against buffer bloat. But it
>> can only effectively work if you're doing traffic shaping at least on
>> your uplink (downlink may or may not be worth the effort depending on
>> your use-case).
>> Additionally, you can lower the priority of icmp-echo-reply this way
>> so during icmp flooding your uplink will still work.
>> This link may help you:
>> https://www.bufferbloat.net/projects/codel/wiki/Cake/
> And this:
> https://github.com/tohojo/sqm-scripts

I haven't mentioned it yet, but several times I've seen the website
perform fine all day until I browse to it myself and then all of a
sudden it's super slow for me and my third-party monitor.  WTF???

- Grant

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