Adding superseed to i2psnark

[immense]

Meaning, when the user is the only seed and there is more than one peer, avoid sending the same piece twice. This improves all peers' download rates, since it makes the peers more useful to each other. See ​http://www.bittorrent.org/beps/bep_0016.html for details.

[zzz]

Sure, a reasonable request, and not the first time it's been suggested, although it's nice to have a ticket for it, thanks.

I've avoided it so far, both because it's low-priority, and it's also tricky to implement it correctly.

For example, although jrandom added rarest-first support to snark 6 or so years ago, it was completely broken until 0.9.3. So only in the last couple months has snark even minimally reduced the seeder bandwidth.

[user]

to make full use of that feature:
after all pieces have been sent once and there are other torrents in i2p, the should be served then, so that the other peers complete among each other, withour the seeder having to send a single piece twice - ideally.
Exception should be if the user wants to upload the torrent as quickly as possible and maybe even leave after completion. In that case he should set the torrent priority to high and it should not "pause" it after the last unsent piece was sent.

[zzz]

see dup #1501 for more info

[user]

darn, i had really overlooked this ticket here. And I had even commented here long time ago, lol.
So, sorry for the duplicate. But maybe/hopefully some of the considerations there are not totally nonsense and help mitigating the disadvantages of super seeding... ;)