Subject: Re: TCP/IP tuning
To: Thomas Miller <firstname.lastname@example.org>
From: Johnny Billquist <bqt@Update.UU.SE>
Date: 02/28/2004 22:30:58
On Sat, 28 Feb 2004, Thomas Miller wrote:
> Christian Biere <email@example.com> wrote:
> > You expect ftp.NetBSD.org to serve you with 5 Mb/s?
> Well, I hear NetBSD is extremely fast. . . . :-)
> > I'd think it throttles connections to a reasonable limit.
> If it's not too impolite to discuss in public, what
> get limit, if any, is enforced on ftp.netbsd.org?
I didn't know there was a limit, except that of course, the bandwidth to
netbsd.org is also limited (there may be a limit on a specific session as
well, and that would be nice to hear, but I'm not on the need to know on
that). However, you can probably safely assume that you seldom are alone
in accessing ftp.netbsd.org, so even though you havea 5 MB/s and
netbsd.org have >5 MB/s, you might not get 5 MB/s, since others are using
the bw of netbsd.org at the same time.
Another aspect you might want to look into is the bw of intermediate
routers. Just because you have 5 MB/s and the other end have > 5MB/s is no
guarantee that you can push through 5 MB/s, since you might pass some
bastard with a 9.6KB/s modem on the way. That would effectively throttle
you to 9.6KB/s even if you have whatever fancy speed at each end.
Finally, never try to use ping to measure anything related to bandwidth.
ping is a tool to measure latency in a network. It's a different topic,
and the tools for this have to do entirely different things compared to
something measuring bw.
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: firstname.lastname@example.org || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol