Does the download speed really go down, when I limit upload?

[con-f-use]

Hi folks,
so I noticed a strange thing. When downloading a torrent, the overall download speed seems to depend on my upload limit. I.e. for a torrent with plenty of seeders like Ubuntu 15.04, I peak at the limit of my ISP connection, which is 8.5 MBit/s. However if I limit my download speed to 30 KiB/s that quickly falls to about 300 KiB/s. I don't have this with transmission or uTorrent. They constantly provide me with maximum download speed regardless of upload limit, provided the torrent has plenty of good seeders. Is that an intentional throttle in Deluge to force people to seed more? If so I find it disturbing and would want a way around it. I'm using the Deluged Daemon v 1.3.6 and WebUI on Ubuntu. Since my server is always on and set to a ratio of 2, people will get their data regardless of my upload speed.
Best Regards,
confus

[doadin]

What your possibly seeing is the fact the the limit counts for "IP overhead" as well. Which is just the communication just by makeing a connection. If theres not enough bandwidth to communicate quickly to peers what you need and what you have then your download will slow down. In other words the seeders are waiting for your PC to say hey i need peice number 1234. And your limit is preventing it from sending many of those requests out. If that makes sense. If you want to test this you can get the LtConfig plugin and set "rate_limit_IP_overhead" to false or unchecked. This may not be the case but thats the first thing id assume given the info you provided. I always run with this unchecked because the amount used is usually pretty minimal but if it ever does need more "communication" bandwidth i dont want my speed limits to affect it.

[con-f-use]

Its a bit tricky to find information on how to install ltConfig. Can you point me to a howto?
Nevermind, you just download the egg, open the WebUI preferences, go to "Plugins" and find the little green logo with "Install" next to it.

Edit:
That seems to have at least improved the situation. The download rate has improved (greatly). Still only about halve the speed I've been having with other torrent clients.

[doadin]

The other thing could be libtorrent. The version that comes with deluge is kinda old and i think some people have had better success with newer versions. Depending on your OS you can try to get or compile a newer version. Other than that without more info cant really help.

Edit i also see you are using an old version of deluge...id look into updateing both.