Can't sustain stable local peer seeding-keeps spiking and dropping

[miffy]

^ I'm seeding using uTorrent (1.8.1, on Windows XP SP2) & it's embedded tracker to transfer another 4GB file from one computer (over a wireless LAN) to another and the transfer speed keeps spiking and dropping. All firewalls on both sides are configured for BitTorrent, and for my seeder, local peers aren't speed limited & I haven't any type of upload limits inplace, either globally or per torrent.

For the receiving computer, its using Transmission 1.34 on Mac OS X 10.5.2.

I can't really tell whether this spiking and droppin is from the seeder side or the receiving side so I hope someone here may be able to help me.

This is my first time using BitTorrent to transfer a file over a local network; its convenient since you can pause at any time and quickly resume, but I'm pretty sure this isn't supposed to happen right?

[thelittlefire]

Looks like initial seeding behavior.

EDIT: Could also be peer errors. Turn on Error > Peer (dis)/connects in the Logger tab. It will show you connect and disconnect messages. It's possible you're experiencing the sporadic IPL error reported before.

[miffy]

what is this "IPL" error?

[thelittlefire]

Invalid packet length.

What did turning on peer connections show in your Logger tab?

[Switeck]

Seems like you've set upload speed max really high in the picture. Was that your regular setting or trying to get the uploading to local peer to go faster?

Transmission likes to request ~100 16KB parts at once, so delays between those requests might cause bursts.

If the Transmission client is trying to download an incomplete torrent, the explanation is simpler: Your client is giving everything it has to the Transmission client in bursts that correspond to whole pieces at once. Many multi-GB torrents have piece sizes of 1, 2, or 4 MB. Once your client gets a whole piece, it would try to send it to the Transmission client.

[miffy]

yea its not posted on the graph, but i disable the upload limits.

also on the logger tab it shows (in reference to the receiving computer) this:

[2008-11-08 21:34:43] 192.168.1.100:49554: Disconnect: No such torrent: B4E56B422E2DE690515FB1E125CD0C01B4E96261

[2008-11-08 21:34:43] 192.168.1.100:49555: Disconnect: No such torrent: B4E56B422E2DE690515FB1E125CD0C01B4E96261

[2008-11-08 21:34:49] 192.168.1.100:49556: Disconnect: No such torrent: B4E56B422E2DE690515FB1E125CD0C01B4E96261

[2008-11-08 21:34:49] 192.168.1.100:49557: Disconnect: No such torrent: B4E56B422E2DE690515FB1E125CD0C01B4E96261

[2008-11-08 21:38:01] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:39:29] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:43:34] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:44:15] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:46:23] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:47:29] 192.168.1.100:51413: Disconnect: Peer error: No connection could be made because the target machine actively refused it.

[2008-11-08 21:51:28] 192.168.1.100:49568: [Transmission 1.34 (73.7)]: Disconnect: Connection closed

this is weird too, since it looks like Transmission changes ports all of a sudden.

also switck, are u implying that having smaller piece-sizes for the torrent would help relieve this? i used the default <autodetect> setting, which utorrent set as 4MB.

i wish also utorrent for mac would come out already :/

[Switeck]

The Transmission client is downloading a 4 MB piece in roughly 30 seconds. Smaller pieces would just mean shorter bursts to the Transmission client, the upload speed would still be about the same. The Transmission client also seems to be trying to download a torrent no longer active on the uTorrent computer.

Port changes are due to uTorrent seeing Transmission's OUTGOING port, not its incoming listening port.

[miffy]

hmm, yeah i tried remaking the torrent using 256kb pieces and it seems the bursts are now just shorter. i dont know how it gets that message ".... Disconnect: No such torrent: B4E56B422E2DE690515FB1E125CD0C01B4E96261". the transmission client has no other torrent started. and utorrent is seeding no other torrent.

[thelittlefire]

Transmission doesn't allow you quite the freedom to look at what's going on. Turn on the Logger window, Apple-3, you can see scrape requests in "debug". You can see announce requests in "info". And of course ERROR shows... everything else.

Just because the torrent isn't "started" doesn't mean transmission doesn't try to connect. Match the infohash to a loaded torrent. Did you recently have it running?

[Switeck]

Have you tried again with Transmission v1.40?

I'd like to know if there's still glaring incompatibilities between it and uTorrent v1.8.1.

[thelittlefire]

IF you're talking about "Invalid packet length", it's not as glaring or consistent on my setup

1.40 seems to stay a bit more stable for upload, but now it includes tracker/peer overhead in the display so it's more accurate but it appears to suffer the same shortcomings as uT for limiting that mechanic automatically... Like if you turn on INFO logging, you can see a persistent spike of traffic for every 10s of torrents announcing, it's possible it doesn't support compact/multiple announces to the same tracker.

[Switeck]

I meant the 100's of canceled messages in uTorrent's logger window caused by Transmission...as an example of glaring problems.