[ILUG] download hiccups after 750 KB or so

[Joerg Baach]

Hi Gavin,

> What is your definition of hiccup?  Do you mean the connection dies
> completely, slows down radically or something else?

Every 750k or so the downloads either stops for 2-3 seconds or the
download actually fails. Something about the connection being reset
(depending on the program I use for the download).

> Did you apply upgrades in the meantime to say, the kernel?  What kernel are
> you running?

Mmmh, as far as I remember the kernel was not updated.

joerg at dars:~$ uname -r
2.6.21-2-686

(Debian testing)

> There are some DSL routers which don't like certain tcp features such as
> window scaling.  I'm not sure if you'd expect this behaviour, but you could
> try turning it off to see if it makes any odds.
> 
> 	echo 0 > /proc/sys/net/ipv4/tcp_window_scaling

I am using a different connection now (different house). The download
does not fail, but there is still a form of slowdown / short stop every
700k - 800k. I also trried the tcp_window_scaling thing, not too much of
a difference, I am afraid.

There is still pattern being repeated in wireshark, even though it seems
to be not quite every 700k - 800k, but at more random intervalls.

[TCP Previous segment lost]
[TCP Dup ACK...] (repeat 30 - 40 times)
[TCP Fast Retransmission]

Mmmpf.

Thanks a lot,

  Joerg