On Thu, 2009-12-10 at 13:08 +0700, Max Arnold wrote: > I've noticed that rsync performs significantly worse than wget on slow > congested wireless > links (GPRS in my case). I don't have large statistics, but in my tests > rsync often stalls > for 3-5 minutes, while wget stalls only for several seconds and then > continues download. > > Is there any rsync protocol features which are sensitive to packet loss and > unpredictable delay? > I understand that rsync transaction has additional metadata transfer in the > beginning (file > list etc.), but after that what can affect the speed? Are there additional > handshakes or > flow control other than tcp ones?
> rsync -rtmz --partial --progress --delete-delay --delay-updates --stats > --itemize-changes > --timeout 120 --contimeout 20 source.example.com::module/file.zip /tmp/ Rsync isn't doing anything fancy that would cause it to be especially affected by packet loss or delay. The protocol takes a few round trips to set up, and then it is largely pipelined, so rsync can tolerate some amount of latency without slowing down the whole process. I can't explain why rsync would stall much longer than wget. The only thought I had is that the network might have a quality-of-service policy that favors port 80. -- Matt -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
