[clug] Something is wrong with my Internet

[Tony Lewis]

We recently moved house and I've been struggling to get my Optus ADSL to 
perform like it should.

I get sync speeds of 4800 up and somewhere between 160kbps-400kbps 
down.  I've tried ADSL2+ and ADSL1.

It seems the connection is very sensitive to uploads.  For example, I am 
currently scp'ing a tar file to a hosted server with plenty of 
bandwidth.  Here's the corresponding ping times to google as things 
progress:

$ ping google.com
PING google.com (172.217.25.174) 56(84) bytes of data.
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=1 
ttl=54 time=52.1 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=2 
ttl=54 time=43.8 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=3 
ttl=54 time=46.0 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=4 
ttl=54 time=44.1 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=5 
ttl=54 time=44.7 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=6 
ttl=54 time=45.0 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=7 
ttl=54 time=52.8 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=8 
ttl=54 time=52.5 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=9 
ttl=54 time=48.9 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=10 
ttl=54 time=674 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=11 
ttl=54 time=745 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=12 
ttl=54 time=969 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=13 
ttl=54 time=1387 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=14 
ttl=54 time=1736 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=15 
ttl=54 time=2087 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=16 
ttl=54 time=2417 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=17 
ttl=54 time=2909 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=18 
ttl=54 time=3289 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=19 
ttl=54 time=3872 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=20 
ttl=54 time=4558 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=21 
ttl=54 time=6284 ms
64 bytes from syd09s13-in-f174.1e100.net (172.217.25.174): icmp_seq=22 
ttl=54 time=6864 ms

It gets real horrible real fast.

I am pursuing things with Optus, but wanted to see if:

  * this was in any way normal?
  * there was anything else I could try to fix things.

Currently I am using Optus' Sagemcom F at st 3864, which is pretty 
universally reviled.  I can't seem swap it out because Optus have locked 
it somehow.  Some think it's through MAC address whitelisting, but 
logically that implies Ethernet packets, and there ain't none going 
between me and them.  It's in bridged mode, which gives me an ATM 
interface on the modem and I can use my linux server as the PPPoE end 
point.  The ATM interface does have a MAC address, though.

I've rooted the modem, so I can telnet in.  It's a cut down Linux 
(busybox-based) and while I can't figure out how to restart the ATM/ADSL 
interface, I can reboot it.

Blindly in the past I've been scripting a reboot every two hours.  This 
seems to help, but now I don't think so.  I was under the impression 
that some process on the modem was leaking memory, or chewing CPU, or 
otherwise being aberrant, because a reboot gave me back good ping times.

But now I think that I got good ping times back because any upload was 
killed or interrupted at least, and so it looked good until that upload 
resumed, then it goes pear-shaped again.

Downloads don't seem to be anywhere near as much of a problem.

I've started logging lots of things, including using pmacct to measure 
my netflows, but I only turned that on last night, so I need more time 
to get useful data.

Any suggestions?

Tony