Why do I get such differing results with competitive P2P clients?

[newconroer]

For the longest time I avoided P2P type networking and downloads. Then about five years ago I got familiar with BitTorrent. Along the way I learned how to maximize output and ensure the appropriate settings.
However I've always had this issue where even on a raging strong torrent, the client will not saturate my download speed (even if I am not uploading anything). If my maximum was 5.5/mbs it would only do for example, 5.2 or 5.3. It was always 200-400kbps lower.
On the plus side, once it's up and into a good connection it holds the speeds, with little dips or variance.

Recently I tested out Transmission and Tixati, with them both hailed as lighter resource use and faster throughput than the Utorrent family clients.

Transmission does at times nearly saturate the bandwidth but it tends to fluctuate speeds often and sometimes very wildly. One moment will see 4.9mb/s and then within seconds it's back down to 2.5mb/s and this entirely random-esque up and down behavior continues.
Tixati has shown to entirely saturate my bandwidth when it manages to peak, in most cases it only gets about half of what I get normally via BitTorrent.

I believe the reason I get a soft-cap in BitTorrent might be something to do with incoming/outgoing ratio. Tixati has this feature, and mine is at 95%/5%. It's possible that BitTorrent's is hard coded in at say 75%/25%?

I know it's not fair to apples to apples these, even when using the same torrent link and the same connection peer limits (and what looks like a good handful of the same exact peers). However I don't understand how with similar settings, I get such varying results.

 

[hellrazor]

Are you measuring the traffic from in the program or out of the program? There is some communication that goes on between peers that the program could count towards download speeds or not count towards download speeds.

 

[Aquinus]

Really? I found Tixati to be slow and clunky where it will hang every time it needs to do disk I/O where Transmission (daemonized on my server) will more easily be able to saturate my 105-120Mbit downstream, probably because it writes asynchronously. Either way I've found the opposite to be true with higher bandwidth. How many peers you're connected to can impact performance as well.

Also, keep in mind that if you're using a torrent with hundreds of seeds and thousands of leechers, it's almost impossible to connect to the same peers both times around.

 

[newconroer]

Are you measuring the traffic from in the program or out of the program? There is some communication that goes on between peers that the program could count towards download speeds or not count towards download speeds.

I am measuring it from within the program. I can download something in BT and get 5mb/s solid, then go download it again with Tixati and get maybe 3/4 of that.

Really? I found Tixati to be slow and clunky where it will hang every time it needs to do disk I/O where Transmission (daemonized on my server) will more easily be able to saturate my 105-120Mbit downstream, probably because it writes asynchronously. Either way I've found the opposite to be true with higher bandwidth. How many peers you're connected to can impact performance as well.


Also, keep in mind that if you're using a torrent with hundreds of seeds and thousands of leechers, it's almost impossible to connect to the same peers both times around.

I only started using Transmission for my NAS box (remotely speaking) and I expect that any variance in speed there might be due to disk I/O. However on my desktops, I didn't expect it to have similar problems.



I'd be happy to stay with BT, but I don't get why it's not using everything available. What else runs off Utorrent(besides Utorrent), that you can recommend?

 

[newconroer]

Something I didn't mention was that the highest speed on the speed graph per torrent, is better than I see in the active torrents window. E.g. it says 4.8mb/s in the DL column, but in the graph chart it may be 5011kbps

 

[v12dock]

I have found that I can max out a connection with Deluge

 

[Nosada]

qBittorrent maxes out a 150Mbit connection easily. That said, I rarely succeed in doing that unless I'm downloading from a private tracker.

 

[Aquinus]

I am measuring it from within the program. I can download something in BT and get 5mb/s solid, then go download it again with Tixati and get maybe 3/4 of that.

Some clients will show you bandwidth including overhead, others do not. If you /really/ want to track bandwidth usage, you need to track it at a lower level. Depending on how many peers you're connected to, the amount of overhead could vary greatly. With that said, I can realize most of my bandwidth with transmission-daemon on my gateway server even using software mdadm RAID-5 which has relatively poor write speeds.

 

[a_ump]

this may sound odd, but I've always found my upload to correlate to my download speed on said torrent. So my max upload is like 120kb/s, max download about 3.1mb/s, if i limit my upload to like 15kb/s(used to have to on my old "high" speed internet), i can only get like 1.5-1.8mb/s down.

Set my upload a little higher ~50kb/s my download can max out. Idk why but i suspect because you have to have so much upload to send "retrieving" requests? just a wild guess but this method holds consistent for me. Don't know if i helped, good luck.

 

[patrico]

so many variable,, trackers (open/priv), clients, your connection, uploaders connection, seeders, peers, location and many variables within those,,
plus other I havnt mentioned,, if your getting full speed off something doesnt mean youll get anywhere near that for the next,,, but if ya do get full speed with a good tracker you should be happy your settings are correct.
Utorrent 1.83 has always been a beast for me,, maxin every isp package ive bought andstill to this day
may the speed be with you

 

[a_ump]

i consistently get full speed as long as the torrent is healthy, even a 1:1 ratio i usually can nab about 1.5-2mb down. Though i never did understand when a big torrent, say 10gb or so, has "stabalized" where no more seeds nor peers are connecting to me, my speed will sometimes pull what i call a wavelength. 3.1mb down....then 2.5mb....1.5>800kbs and then it'll shoot back up to 3.1mb. all within a matter of seconds. Funky stuffs