Bit Torrent D/L Speed..

techguy

Is this proportional to the amount you have uploaded or does it matter whether you upload or not..
Or is the speed completely dependable on you and your peers speed?

Hakko

fatherdougalmag

I've firmly come to the conclusion that it is nothing to do with your u/l speed. I use Azureus and sometimes clamp the upload speed otherwise my VoIP service suffers. Even with u/l clamped to 3kB/s I have been downloading at 200kB/s (NTL). When looking at the peers I can see that it's typically down to a good seeder. In fact, a friend was having crappy d/l speeds and then he clamped his u/l at a lower speed and noticed improved performance. For whatever reason, I do notice that when u/l bandwidth is congested it can have a negative effect on (non-Bittorrent) d/l performance. Might be something imposed by the ISP.

techguy

Im on eircom, sigh... and I have never got anything above 70 kb/s even with nothing else using the connection..the norm is about 20-30 kb/s.
Crappy or what..?

okcomputer

hakko1872003 wrote:

Im on eircom, sigh... and I have never got anything above 70 kb/s even with nothing else using the connection..the norm is about 20-30 kb/s.
Crappy or what..?

I reguraly see 100kb/s + on NTL

Tony H

sometimes get up to 140-150 kb on eircom

techguy

but is that on btorrent fitz?I can get that sometime when d/l ing form HTTP..
Also are you in dublin or another city..
I'd say that eircoms boradband is better in cities because there is competition..
In the likes of Tipperary where I am there is very little or no competition but I may be wrong.My contract is up in january anyway so I will review my options then..

Gone West

fatherdougalmag wrote:

I've firmly come to the conclusion that it is nothing to do with your u/l speed. I use Azureus and sometimes clamp the upload speed otherwise my VoIP service suffers. Even with u/l clamped to 3kB/s I have been downloading at 200kB/s (NTL). When looking at the peers I can see that it's typically down to a good seeder. In fact, a friend was having crappy d/l speeds and then he clamped his u/l at a lower speed and noticed improved performance. For whatever reason, I do notice that when u/l bandwidth is congested it can have a negative effect on (non-Bittorrent) d/l performance. Might be something imposed by the ISP.

Thats your conclusion so?
Congrats.
Pity its absurdly incorrect.

Bittorrent trackers set the rules.
Depends on the tracker(think website, if you dont understand). Some cap what you can get back, if you dont upload, others dont have restrictions.
Certain private ones use user account ratios in other ways. I can often max out my 100 megabit line on bittorrent.

Also you seem to misunderstand the concept of peer to peer filesharing...
For it to work effectively, each person should be uploading a 1:1 straight ratio to what they download.

Leeching is good for the individual, but bad for the collective individual.
for shame, etc.

Ruaidhri

Also,i've noticed that the limited upstream (128K) has a VERY adverse effect on downstream. Limiting your BT client to 7k up seems to be the sweet spot,it opens up enough of the upstream to ACK packets coming down in a timely fashion.

techguy

So Shall I set my up speed to 7kb/s..for some reasonable down speed?
Also I download all my files into a bit torrent folder then move them into their proper folders when downloaded.But then Azureus cannot find the file when it is moved.Can I tell azureus where it has gone to or should I choose the d/l path as the place where I will be leaving the file?

Thanks..

fatherdougalmag

FuzzyLogic wrote:

Thats your conclusion so?
Congrats.
Pity its absurdly incorrect.

It's an observation. I'll admit I don't know fully the BT protocol top to bottom but I based my reply on anecdotal evidence. Specifically citing examples where I have downloaded files at 200kBps even when my upload was limited to 3kBps.

Also you seem to misunderstand the concept of peer to peer filesharing...
For it to work effectively, each person should be uploading a 1:1 straight ratio to what they download.

Leeching is good for the individual, but bad for the collective individual.
for shame, etc.

Eh ... where exactly did I suggest I was leeching or mention ratios? You assumed that because I limit my u/l I leech. I still limit my upload at 3kBps and seed the torrent after the download has completed for me.

Gone West

fatherdougalmag wrote:

Eh ... where exactly did I suggest I was leeching or mention ratios? You assumed that because I limit my u/l I leech. I still limit my upload at 3kBps and seed the torrent after the download has completed for me.

Thats exactly my point.

The principals of how BT works is that a file is broken into pieces, the uploader sends these pieces out, in linear order or if in super seed mode, where needed (never super seed, just causes too many problems!)

if you have four peers and one uploader, with the uploader setting their client to connect to four peers, each peer will receive a differnt piece, most likely in order, peer one statistically will receive pieces 1, 5, 9, 13, 17

so this means that whilst downloading the pieces of the torrent off the uploader, you want to be downloading the pieces already given out by the uploader. and in turn, those peers want every other peers pieces.

i am going to describe two broadband lines and average speeds you will see, and beginner with one of these two lines has it easy now.

512/256 you can download at 50/51kbs whilst uploading 20kbs at the same time 1meg/256 you can download about 100/102 whilst uploading 20kbs at the same time.

plan ahead! are there only a few peers on the torrent and the torrent is large, like dvd size or larger? should you be better to cap your download speed with Netlimiter so you aren't taking in too many pieces at once, that you can't pass back out to other peers?

are you bored waiting and go start another smaller torrent while you are waiting (that won't work, now your upload speed is divided between two torrents, making the problem worse!)

has the uploader decided that with their fantastic foreign line that they will upload 4 dvd's worth of data at the same time? are you starting to panic, thinking that with your line, by the time you get the first torrent, and pay back, the next torrent won't be working anymore?

so, what are you going to do? jump on all 4 torrents? give an average upload speed of 5kbs to each torrent? not care about damaging the speeds of the torrents, because "cool torrent mate! i'll keep my client open for weeks to keep this beuaty alive!" yeah, well at 5kbs you will need weeks to pay all the torrents back.

this is where everyone has to understand a very simple fact about torrents, that sadly many people are choosing to ignore.

by not uploading the pieces you received from the uploader, YOU are damaging the torrent. YOU are doing it, it's YOUR fault.

Limiting your upload and seeding later, as I've just shown is almost as bad as straight leeching.

fatherdougalmag

Well thanks for the bluffer's guide to the BT protocol fuzzylogic. I'm certainly more the wiser because of your post. It'll probably help others get a better idea of the importance of being more generous with their upload. For the sake of the torrent, I'll do my best to grant my full upstream bandwidth when torrent'ing but we have switched to VoIP and I need to be careful as it can screw our telephony up big time when the upload is @ 100%/unlimited.

Gone West

Just upgrade your routers firmware/upgrade router to something that can handle packet prioritising/traffic shaping based on port. Put your VoIP ports as #1 priority. that way, you can leave upload on full, but when using VoIP it always gets enough bandwidth.

Cheers btw.

fatherdougalmag

That's the pissy thing. I got a QoS router (Sipura) from Blueface and it's "in front of" my router so it should be QoS'ing the connection anyway. Maybe more of an issue for the VoIP forum. Or switching to a different less intensive/G.729 codec on the VoIP service might help out.

But going back to the OP, can you give more insight to us on maximising download throughput? Especially where the service is typically asymmetric? Is it really down to the tracker or is it a combination of tracker and peers with oodles of upstream bandwidth? I had always thought that the more generous you were with u/l, the better d/l performance you'd get. But after having to limit the u/l I noticed that it didn't have any negative effect on d/l. Granted the ethos of BT and u/l'ing as much as possible, is it better to concentrate on one torrent at a time and grant as much u/l as possible?

Gone West

It really does depend on the tracker.
The top 10 bittorrent sites nowadays.(dont think I can name/link em.) all use a whole bunch of public trackers. The tracker admin sets the rules. Some will kick you off or give you incorrect data if youre not uploading.

A lot though are just standard. Upload what you can, download what you can.
What you want is private BT trackers. I can and have maxed out any line I've had on one particular private BT site.(ie, Ive gotten 6.5k on 56k modem and 11000kb/sec on a 100megabit line, and everything in between)

But in general, BT is slow. Theres not a whole lot you can do to make others turn off their limiters.
Might I suggest other protocols for getting your data.
ftp,irc,dc++ etc

techguy

So if I want to share my files..I create a torrent in azureus and upload it to the tracker I have just signed up to..it will appear in their list. But how do they know how much I have uploaded etc from that?