Hi,

Now that 2.0 is out, I'm trying (again) KTorrent. But I'm hitting a problem: ktorrent download speed is very low compared to either Azureus or BitTornado.

My ADSL connection allows about 12 kB/s up, 58 kB/s down. Both Azureus and BitTornado connects quickly to a lot of peers and uses all my bandwidth in a few minutes. KTorrent connects very slowly to peers, starts downloading quickly but rarely reaches above 30 kB/s down.

Even though I have set it to 120 connections max per torrent and 800 connections global, with lots of peers on swarm, KTorrent keeps connected to about 30-40 peers... I have to Manually Announce many times for KTorrent to connect to more peers.

Of course, download speed is not capped, ports are not firewalled. Looking on bugs.kde.org, it seemed similar to this bug: http://bugs.kde.org/show_bug.cgi?id=111050 , but it seems to be already fixed in 2.0.

It seems to be something related to how aggressively KTorrent asks peers for pieces, but I'm not sure.

Thanks for any help.

MilesMi wrote:My ADSL connection allows about 12 kB/s up, 58 kB/s down. Both Azureus and BitTornado connects quickly to a lot of peers and uses all my bandwidth in a few minutes. KTorrent connects very slowly to peers, starts downloading quickly but rarely reaches above 30 kB/s down.

I have seen KTorrent gettting 30mbit/s download on a torrent, and on my own connection 11mbit/s download is no coincidence.
I think the slow connecting to peers *could* be related to the many "authentication failures" in log, though i assume they're not there for no reason.

Even though I have set it to 120 connections max per torrent and 800 connections global, with lots of peers on swarm, KTorrent keeps connected to about 30-40 peers... I have to Manually Announce many times for KTorrent to connect to more peers.

KTorrent should download fine with 25-30 connections max per torrent set. More connections is no rule for success.

You might want to try and check the number of upload slots.
Seeing your upload it not that much, i would try to give each peer 2-3 KB/s. Four upload slots would be something to try, any more slots would probably not do you any good.

It seems to be something related to how aggressively KTorrent asks peers for pieces, but I'm not sure.

I've read rumours and complains about that on forums yes. I think the question here is: Is this on the KTorrent code or is it someone who wants to behave like this? And if it is on KTorrent code, how much a problem is it?

Well, the amount of outstanding requests for pieces per peer is between 10 and 25 (the faster the peer, the more requests we send it).

The idea is to keep the other side busy, but maybe that's a bit too aggressive ? I will do some experiments with lower limits.

Hi!
I'm pretty new to KTorrent (I got sort of used to BitLord on Win) and I find it amazing, and it just keeps improving very, very fast. After using 1.1 and then 1.2 for a while I decided to upgrade my internet connection from 32KB to 128KB. Back then I was gettin' around 20-25 KBs, which was pretty good comparing to other clients I had used before (on Win), actually only second to BL (but with many more features .

The thing is... that's about the speed I still get, with 4X the bandwidth.
I read that speed-related problem were fixed on versions 2 (betas and so), so I got KT 2.0. It has even MORE features, but the speed thing is still there.
I tried with very popular torrents (over 1000 sources total, 200 at once, over 50% seeders), and connect to around 30-40 peers (good). Nevertheless, I get about 1KB per peer or less. The average must be around 15 with RARE peaks of 30.

I generally see that around 40% of peers (goes from 0 to 70%) are choked and another 30% or so snubbed, leaving a clean ~30% that somehow don't upload anything, or if they do (a minority) only do so below 2KB/s. Is it them?

Another thing is in the "Peers" window tab... what's with the IPs with locks?? Are those peers firewalled? Why do choked peers remain in the window for so long? I have the memory usage option on high, could it be thath I am sharing too many torrents at once (4-6)?

Or maybe is it that the whole Bittorrent thing got TOO POPULAR, in the way that too many "bad peers" are today using it? You know, the typical "1KB up rate with 1Mb connections" and such...

I'd appreciate any help.
And I'm willing to read any tutorials or whatever I need to do, just point me in the right direction.

Thanks in advance.

PS: I almost forgot, I'm running KTorrent 2.0 on Kubuntu 5.10, Athlon 64 2G. BWidth: 128KB/32KB (u/d). And my Upload is perfect, in fact all my Share Ratios are above 1.00.

I have been using ktorrent for a few days now, and I must say, it is much better than I expected, feature wise. Furthermore it is a KDE app (yeah, no more need to have an ugly gtk or swt app !) and a really lightweight bt client compared to other clients for linux.

However, there is no mistaking : ktorrent's download is way slower than the official client !!! (or its derivatives like bittornado). Download speed lags far behind upload speed, and not only as a border effect. For instance, in a torrent I have been downloading recently, I received 3GB while I sent 9GB !!!

I don't know every detail of the bt protocol, but when I see the peer list in ktorrent, I see that among the peers that I am uploading to, only one or two get 99% of the upload limit bandwidth. I believe other clients divide the bandwidth with more fairness. If more peers would actually receive something from me, more would allocate one of their slots for me, and my overall download speed would be greater.
George, have you tried to tweak those parameters ?

I think this speed problem is the greatest drawback of ktorrent. Are you working on this ?

Anyway, I wish you good luck with this piece of software !
Regards.

[edit] : it seems this slowness problem has been adressed in bugs.kde.org... and it is written as RESOLVED (in 2.0 beta). AFAIAC the bug is still here in 2.0.1, along with this "jumpiness" of the speed : one instant you have 50, one second later 25, then 35, 55, 20, ... Other clients seem to be more regular.