We need a sticky set of port forwarding instructions so we don't keep getting "slow download" reports. Some files are throttled-back but most of the time people have no idea how to forward a port...I didn't at first either.

http://ktorrent.org/forum/viewtopic.php ... highlight=
has some good instructions. More are needed including links to screen shots.

Lance

I'm fine with that.

Is there anybody free to make such a thread? I can do it but due to the lack of free time, I'm not sure when will it happen.

Please give this a read, make any changes & sticky post as you see fit. I probably needs a subject line like: Slow Downloads!

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There are two main reasons for slow downloads (well three reasons if you include a slow connection, but I assume you know if you're using a 300 baud dial-up modem!).

A hardware or software firewall:
This is the most common problem. You probably have at least one firewall, maybe a few: Even on a small home/office system you probably have one in your Cable or DSL gateway (or modem), one more in your router, plus a software firewall running on each computer! You must forward torrent ports through those firewalls:


KTorrent's default setting are common for older torrent clients:

a) In "settings" the one labeled simply "port" should be set as TCP. Traditionally using any port or range of ports from 6880-6889. You can put one single port like, 6880-6880 (since the ending number is the same as the starting number, this specifies one port). Sometimes (particularly with a cable company ISP) you must get creative, try a port number or short range somewhere around 40000 or 50000.

b) The one labeled "UDP tracker port" is obviously UDP, and needs to be a different port number. Something near 4444 is very common.

c) The third one, "DHT", is also a UDP port. Again a different port number is required numbers near 6880 or 444 are common, but remember: all 3 port settings must be different actual numbers!

Here are some additional resources about how to forward your ports through those firewalls:

http://compnetworking.about.com/od/bitt ... tports.htm
http://www.portforward.com/
http://www.homenethelp.com/web/explain/ ... ng-dmz.asp


Slow or scarce Peers:
These are the second main reason for slow downloads. Older software .iso's, audio books and radio theater recordings are particularly "under seeded" and "throttled-back". There's not much that can be done about this. You can search for a better seeded version, that's about all.

It's good for a start

Nowadays with the 2.1 series, majority of the reason for 'slowness' is not because of our client but just because of the bittorrent protocol and its interactions with various network situations.


When you get weird issues with network activity (including other programs) coming to a standstill, you should also question if your router is being overloaded. Turn off DHT, as the UDP communications used by DHT occupies a large number of routing tables.

If you are torrenting over a wi-fi connection, I've found that wifi connections tend to slow down when under BitTorrent-like load. Really reduce the # of peers you're connecting to, or find a wired plugin

Note, concerning the UDP tracker port, I'm thinking it might not be necessary to forward the port. Seeing that in essence it's a request - reply kind of thing, most NAT routers are probably configured to let traffic like this pass.

George wrote:Note, concerning the UDP tracker port, I'm thinking it might not be necessary to forward the port. Seeing that in essence it's a request - reply kind of thing, most NAT routers are probably configured to let traffic like this pass.

Routers tend to be horrible with their ability to track UDP packets reliably without the use of explicit forwarding though... According to Azureus folk, lots of routers only have 255 openings for UDP mappings and one can quickly exhaust that unless a static mapping (port forwarding) is used.

Here's a (way rudimentary) site on determining whether you're behind one or not:
http://www.its.queensu.ca/itsc/faq/webc ... ewall.html

Anyone have something better, or any resources to find out if it's your machine or the network that's blocking ports?

Here are some tips to fix this.


http://torrentfreak.com/20-bittorrent-t ... ks-070903/

Peace

My apologies, but I followed links above, got sidetracked, so I can't say who deserves the most thanks.

Anyway - whichever link lead me to it, THIS calculator improved download speed dramatically:

http://infinite-source.de/az/az-calc.html

The recommendations were contrary to what I thought, or assumed, or had learned. I applied the recommendations just to see what would happen, and they work.

Good thread, and thanks to everyone.

If you ignore the issue of media speed (dial-up vs DSL vs cable modem, etc.), does the number of active torrents you are downloading affect your total download throughput? In other words, when a client is deciding who to send data to, does it consider how many different torrents the peer is currently handling?

I understand some trackers use an upload/download ratio to rank peers, but do the clients themselves consider any kind of ul/dl ratio when deciding who to upload to?

I notice that ktorrent allows you to attach several trackers to a torrent. Does ktorrent actually use all of the trackers on the list, or is only one tracker actually used? Does multiple trackers help with improving the download speed?

picker wrote:I notice that ktorrent allows you to attach several trackers to a torrent. Does ktorrent actually use all of the trackers on the list, or is only one tracker actually used? Does multiple trackers help with improving the download speed?

Yes, multiple trackers do help improve speed when there are connectable peers on the other trackers in the list.

I actually came across this topic from a google search. I've been wondering about this too. It seems it only uses one tracker at a time--for example, I uploaded something to two different private trackers, but while I'm seeding on one tracker, the other site lists 0 seeders.

A good tip for improving speeds if you have some suspicious slow speeds using ktorrent 3.0.2 ( I don't know if it's specifically RH Fedora 8 and 9 rpm's), downgrade to version 2.2.2.

On the same torrents v3.0.2 suffers so bad the speeds are around 40-60KBps at an average sometimes even as low as 10-20KBps whilst version 2.2.2 gets 600-1200KBps average (I have a 15mbit connection).

I have not yet seen v3.0.x max out my connection but I've seen it several times with version 2.2.x

Jesper wrote:A good tip for improving speeds if you have some suspicious slow speeds using ktorrent 3.0.2 ( I don't know if it's specifically RH Fedora 8 and 9 rpm's), downgrade to version 2.2.2.

On the same torrents v3.0.2 suffers so bad the speeds are around 40-60KBps at an average sometimes even as low as 10-20KBps whilst version 2.2.2 gets 600-1200KBps average (I have a 15mbit connection).

I have not yet seen v3.0.x max out my connection but I've seen it several times with version 2.2.x

I do not think there are any changes made to libbtcore here between the two versions.

My speed in ktorrent 3.1 is very slow in comparison to other clients.

For example there is a torrent I'm downloading for at least one week now. The size is about 3.4GB and until today I downloaded it for a couple of hours every day. There are something about 400 seeds and 1000 leecher. The average speed in ktorrent was 33.41KB/s. I'm on a 3Mbit connection with a max of 356KB/s downloadspeed so this is not what I would call fast

Today I tried out Deluge and qBittorrent and both clients have much better download rates for the same torrent. The speed in qBittorrent is exactly 161.6KB/s right now and it always keeps above 120KB/s. I also have to mention that I applied exactly the same settings (max. conn, speeds...) on all clients.

One thing that caught my attention in ktorrent was the fact that on this torrent with so many peers available I had only connection to 30-40 of them (out of 1400). On qBittorrent its 109 peers.

This is very sad because I love ktorrent and got very used to it now but with this issue I'm sticking with qB for some time now.
Is there something I could do to help resolve this problem?