Subject: Re: TCP/IP tuning
To: Thomas Miller <tom@insolvencyhelp.org>
From: Johnny Billquist <bqt@update.uu.se>
List: current-users
Date: 03/02/2004 12:38:03
On Mon, 1 Mar 2004, Thomas Miller wrote:

> Johnny Billquist <bqt@update.uu.se> wrote:
>
> > Interesting. What ping times do you have?
>
> Hi Johnny,
>
> 5 packets transmitted, 5 packets received, 0.0% packet loss
> round-trip min/avg/max/stddev = 19.343/20.503/22.315/1.390 ms

That was rather much. Okay, so then we know that you have some latency,
and a larger sliding windows will improve the situation. But, as you
noticed, doubling improved it, but beyond that, there was no change, so by
then you were getting as much data as you possibly could. The bottleneck
is then no longer at your end. It's either the ISP ftp-server, or the
ADSL-modem, or some router in between that don't feed you more data.

(As a comparision, a large ftp-server, which is not exactly next-door, but
still in Sweden, gives me a ping-time of about 17 ms, and that is 14 hops
away.)

> > It would also be interesting to know exactly how your ISP
> > is limiting you to 5 MB/s.
>
> One of the ISP folks said there is a setting in the modem
> which they access remotely.  Sorry, I realize that's not
> very informative.

:-) Your ISP folks probably don't even know what we're talking about.

> > But it don't really make sense that your two sessions
> > should get so  different rates.
>
> Please help me to understand why you think 2 or 3% is
> significant in this context.

Huh? Correct me if I'm wrong, but didn't you say 240 KB/s and 160 KB/s.
That's nothing like 2 or 3%...

> > pdp is alive!
>
> Cool!  :-)

(Try telnet:magica.update.uu.se :-) )

	Johnny

Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt@update.uu.se           ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol