[Please Cc me on replies.]
Dear Debian folks,
In the Eduroam Wi-Fi network of the TU Chemnitz (X-WiN, Cisco CW9164i,
CW9166i, C9124AXE-E) I noticed too low download speeds from Debian
archive mirrors. Using a cable full adapter speed is achieved, so it’s
not some bottleneck in the peering. Later I also noticed this in other
Wi-Fi networks (Versatel), though I couldn’t verify with a cable there.
This also happens with non-mirror HTTP servers, but I have no idea, who
to ask, so I am writing to you.
Download speed over Wi-Fi for most mirrors [1] was limited to 30 MB/s –
for example ftp.de.debian.org (TU Dresden (X-WiN), Apache/2.4.62
(Debian)). Only with deb.debian.org (Fastly, varnish) I got 43 MB/s.
Later tests, not at TU Chemnitz, show that mirrors.xtom.de (nginx) is
also much faster, where download speed of mirrors.xtom.de is greater
than Fastly’s one. As full speed is achieved with cable, it shouldn’t be
related to the Web server software in use.
This is reproducible on different systems (Dell XPS 13 9360 with
Qualcomm QCA6174, Macbook with macOS) and with GNU Wget and curl. Also
it’s reproducible in different Laptops and with different providers
(Eduroam X-WiN, Versatel) and access points (Cisco, Ruckus).
I never noticed because I mostly use cable connections, and often
Internet speeds over 25 MB/s are not common for the Wi-Fi networks, I use.
1. Can you reproduce that?
2. Do you have an explanation? What do mirrors.xtom.de and Fastly do
differently?
Kind regards,
Paul
[1]: https://www.debian.org/mirror/list
$ wget -O /dev/null
http://ftp.de.debian.org/debian/pool/main/f/flightgear-data/flightgear-data-base_2020.3.19+dfsg-1_all.deb
--2025-03-23 11:29:51--
http://ftp.de.debian.org/debian/pool/main/f/flightgear-data/flightgear-data-base_2020.3.19+dfsg-1_all.deb
Auflösen des Hostnamens ftp.de.debian.org (ftp.de.debian.org)…
141.76.2.4, 2a13:dd80:deb::deb
Verbindungsaufbau zu ftp.de.debian.org
(ftp.de.debian.org)|141.76.2.4|:80 … verbunden.
HTTP-Anforderung gesendet, auf Antwort wird gewartet … 200 OK
Länge: 914066216 (872M) [application/vnd.debian.binary-package]
Wird in »/dev/null« gespeichert.
/dev/null 32%[=======> ] 283,09M 28,6MB/s
ETA 21s ^C
$ wget -O /dev/null
http://deb.debian.org/debian/pool/main/f/flightgear-data/flightgear-data-base_2020.3.19+dfsg-1_all.deb
--2025-03-23 11:30:04--
http://deb.debian.org/debian/pool/main/f/flightgear-data/flightgear-data-base_2020.3.19+dfsg-1_all.deb
Auflösen des Hostnamens deb.debian.org (deb.debian.org)… 146.75.122.132,
2a04:4e42:8e::644
Verbindungsaufbau zu deb.debian.org (deb.debian.org)|146.75.122.132|:80
… verbunden.
HTTP-Anforderung gesendet, auf Antwort wird gewartet … 200 OK
Länge: 914066216 (872M) [application/vnd.debian.binary-package]
Wird in »/dev/null« gespeichert.
/dev/null 10%[=> ] 95,73M 39,1MB/s
^C
