"Initial Seeding" causes upload speed to spike strangely

[sinoth]

My ISP is AT&T Uverse. I tried seeding a torrent using "Initial Seeding" and this is what my upload speed graph looked like:

Looks like ISP traffic shaping, huh? I was so convinced AT&T was doing this to me that I spent the afternoon trying to prove it. Long story short, it turns out the "Initial Seeding" option in uTorrent 1.8.3 was causing these funky spikes. Exact same torrent WITHOUT "Initial Seeding" produces this upload speed graph:

This seems like an error to me, but who knows.. maybe it is how it should be for whatever reason. Just wanted to bring it up.

[Ultima]

Initial seeding isn't perfect in µTorrent, which can play some role in that pattern. In the end, though, it isn't unexpected that initial seeding would cause that to happen. Initial seeding is more selective about what pieces it sends out, so of course it has a lower chance of keeping the upload rate at maximum -- you're not necessarily sending out the pieces other peers are actively requesting.

[Switeck]

Initial seeding essentially requires 3 willing peers minimum to work correctly.

Peers that refuse to upload to others OR are using sequential downloading are not "willing" peers for this purpose.

[Oxwil]

My upload goes higher in initial seeding mode as long as there are willing peers to whom I can upload to easily. Otherwise, my upload is dead slow.