first, it appears that no window scaling is implemented or enabled by default on 5.0.
then, it appears that you can't even set the default tcp buffer size to 256K, or stuff simply won't work.
from there, it appears that after you do set the buffer size to something like 224K (net.inet.tcp.recvspace=229376), doing pkg_add kdebase4 will reach the mclpool limit, and your networking capabilities are kaput.
well, yeah, at least this fuck up is documented, but then note that the sysctl variable is not runtime modifiable (at least on i386), so you have to edit the /netbsd with gdb and reboot the system before you can actually have `pkg_add kdebase4` complete.
and, last but not least, i'm quite disappointed in the praised infrastructure of the netbsd project: there's a nice mirror at columbia.edu that I can get 100Mbps from, nyftp.netbsd.org (Columbia, NY, 19ms away), but it only carries the daily builds and the packages -- I cannot find any decent mirrors that carry git, cvs and the normal ftp files that I would get over 40Mbps from here at UWaterloo.
just fyi: as of now, at UW we have a 1Gbps link to the educational network (including all the US universities) and a 1Gbps link to the internet. both freebsd and openbsd do have the nearby educational mirrors that provide speeds of 100Mbps over here, ftp-archive.freebsd.org (at Buffalo, NY, 7ms away) and obsd.cec.mtu.edu (MI, 20ms away). note that to get 100Mbps with 224K buffer size you have to be at least as close as 19ms from the mirror.
100Mbps in action:
hype:tmp {562} date
Thu Nov 5 17:40:27 EST 2009
hype:tmp {563} ftp ftp://ftp-archive.FreeBSD.org/pub/FreeBSD/ISO-IMAGES-i386/8.0/
Connected to moss.cse.buffalo.edu.
220 ftp-archive.freebsd.org FTP server (Version wu-2.6.2(1) Fri Jun 12 09:41:08 EDT 2009) ready.
331 Guest login ok, send your complete e-mail address as password.
230 Guest login ok, access restrictions apply.
Remote system type is UNIX.
Using binary mode to transfer files.
200 Type set to I.
250 CWD command successful.
ftp> ls
150 Opening ASCII mode data connection for /bin/ls.
total 3664980
-rw-r--r-- 1 89987 546 44777472 Oct 26 13:09 8.0-RC2-i386-bootonly.iso
-rw-r--r-- 1 89987 546 655726592 Oct 26 13:10 8.0-RC2-i386-disc1.iso
-rw-r--r-- 1 89987 546 1870997736 Oct 26 13:13 8.0-RC2-i386-dvd1.iso.gz
-rw-r--r-- 1 89987 546 256112640 Oct 26 13:14 8.0-RC2-i386-livefs.iso
-rw-r--r-- 1 89987 546 923340800 Oct 26 13:03 8.0-RC2-i386-memstick.img
-rw-r--r-- 1 89987 546 326 Oct 26 16:14 CHECKSUM.MD5
-rw-r--r-- 1 89987 546 501 Oct 26 16:14 CHECKSUM.SHA256
226 Transfer complete.
ftp> get 8.0-RC2-i386-bootonly.iso
local: 8.0-RC2-i386-bootonly.iso remote: 8.0-RC2-i386-bootonly.iso
150 Opening BINARY mode data connection for 8.0-RC2-i386-bootonly.iso (44777472 bytes).
100% |******************************************************************************************| 43728 KB 00:04
226 Transfer complete.
44777472 bytes received in 4.05 seconds (10.54 MB/s)
ftp> quit
221-You have transferred 44777472 bytes in 1 files.
221-Total traffic for this session was 44778897 bytes in 2 transfers.
221-Thank you for using the FTP service on ftp-archive.freebsd.org.
221 Goodbye.
hype:tmp {564} traceroute ftp-archive.FreeBSD.org
traceroute to moss.cse.buffalo.edu (128.205.32.24), 64 hops max, 40 byte packets
1 dccore-nsfw02-csresearch1net.uwaterloo.ca (129.97.7.1) 0.452 ms 0.246 ms 0.300 ms
2 172.19.5.1 (172.19.5.1) 0.596 ms 0.567 ms 0.536 ms
3 v720-cn-rt-phy.uwaterloo.ca (129.97.1.77) 0.624 ms 0.556 ms 0.574 ms
4 ext-rt-mc-cn-rt-phy.uwaterloo.ca (129.97.1.10) 0.560 ms 0.559 ms 0.522 ms
5 66.97.28.65 (66.97.28.65) 0.503 ms 0.564 ms 0.566 ms
6 66.97.17.78 (66.97.17.78) 3.160 ms 3.155 ms 3.151 ms
7 66.97.17.45 (66.97.17.45) 5.724 ms 6.534 ms 5.827 ms
8 199.109.11.25 (199.109.11.25) 6.683 ms 6.609 ms 6.681 ms
9 sunyab-buf-7600.nysernet.net (199.109.11.6) 7.47 ms 6.906 ms 6.857 ms
10 rtr-internet9-93.cc.buffalo.edu (128.205.9.93) 7.418 ms 7.131 ms 7.118 ms
11 l3sw-cc9-82.cc.buffalo.edu (128.205.9.82) 7.557 ms 7.474 ms 7.332 ms
12 vss-cc-bell9-246.cc.buffalo.edu (128.205.9.246) 8.12 ms 7.779 ms 7.808 ms
13 128.205.9.233 (128.205.9.233) 8.187 ms 7.969 ms 7.843 ms
14 moss.cse.buffalo.edu (128.205.32.24) 7.383 ms 7.430 ms 7.284 ms
hype:tmp {565} sysctl net.inet.tcp.{recv,send}space
net.inet.tcp.recvspace=262144
net.inet.tcp.sendspace=131072
hype:tmp {566} uname -rms
OpenBSD 4.6 i386
hype:tmp {567}
