Dear Joachim and all mentainers: I have more information on this bug. When I changed ~/.cabal/config file to use
remote-repo: old.hackage.haskell.org:http://old.hackage.haskell.org/ instead of remote-repo: hackage.haskell.org:http:// hackage.haskell.org/packages/archive cabal update successed; When I changed back to default, the issue is then reproducable again. In both case, proxychains cabal update will get segmentation fault. Hope it helps. Best, Zengbo 2013/11/4 张增波 <zengbo.zh...@gmail.com> > HI Joachim and all, > > I guess two situations may help to reproduce it: > > 1. I am behind two NATs, one is a home router, one is the connection point > from ISP to Internet (maybe more, depends on ISP). > 2. The network speed is slow from my pc to hackage server (about 10KB/s) > > And there is another phenomenon after I reported the bug: I tried again (3 > times) to do cabal update, with two times get partial content (almost full, > let me say, only ~200k lost compared to a wget-ed and verified version but > I didn't record the number ) after about 10 minutes then it reported the > tarball is broken; and the last time it hangs with 3 hours so I did Ctrl-C > to exit (same as the bug report itself). If you need I can do more times > and give some accurate data (time/size). > > From the new phenomenon, I guess again it is about a weak design of tcp > itself: when there is only one direction of data flow, the sender may close > the tcp link more quickly than the receiver at certain condition: for some > point the sender lose all data packages (and re-transmissions) to the > receiver, and the receiver don't know it at all. Although it is a tcp > weakness, AFAIK, this should be overcome by some upper layer protocol > implementation. > > And another thing I am surprised is about proxychains, it is 100% > segmentation fault on my side. I just use a ssh dynamic port forwarding and > in wget case it can speed up the download to hackage server. It should be > easy to reproduce in my opinion. > > Best, > Zengbo > > > 2013/11/4 Joachim Breitner <nome...@debian.org> > >> Hi, >> >> Am Sonntag, den 03.11.2013, 19:41 +0800 schrieb Zhang Zengbo: >> > I am a new user of haskell-platform. After I installed it, I simply run: >> > cabal update, it hangs, then I try to use --verbose=3 to see what >> happend: >> >> unfortuately, I cannot reproduce it here. Is there anything special >> about your network setup? E.g. forced proxies or something of the kind? >> >> Greetings, >> Joachim >> >> -- >> Joachim "nomeata" Breitner >> Debian Developer >> nome...@debian.org | ICQ# 74513189 | GPG-Keyid: 4743206C >> JID: nome...@joachim-breitner.de | http://people.debian.org/~nomeata >> >> >> >