16-KiB piece size

[nightshifted]

Am I imagining it, or does µTorrent reject torrents where the piece size is 16 KiB (or 16 kB for those of you who dislike the -i- notation)?

1.1.7.2, 1.2, and 1.2.2 all reacted to such a torrent with a popup that read (quotation marks are literal),

· Unable to load "foo.torrent". File is not a valid torrent file!

(Edit: actually, only 1.1.7.2 included that second sentence.)

When I edited the piece length integer to 32768, µTorrent opened it happily; of course, that changed the info_hash, so it couldn't get into the swarm.

Mainline, Azureus, and BitComet didn't mind the original at all.

This behavior was the same with the three versions of µTorrent I listed.

[ludde]

This is correct, µTorrent currently limits to 32k. That is to discourage using too small pieces.

I could lower the threshold to 16k instead of 32k

[nightshifted]

Thanks for answering, Ludde. I've no preference and am not requesting such a change, just wondering whether the piece size was what caused the error message. The various .torrent creation programs I've personally seen don't support making pieces smaller than 32 KiB anyway. The automatic size selection in many of them sometimes tends to choose larger pieces than I would, but 32 KiB is never too large.

If nobody can report having seen smaller pieces on actual torrents in the wild, the floor might as well stay as it is. (This torrent with the 16-KiB pieces has been replaced with one where the pieces are 32 KiB.)

[Ares]

Possibly it should support using torrents with piece sizes lower than 32KiB, but not creating anything lower than 32KiB? Because I believe I've ran into this problem before, but I thought it was just a corrupted .torrent file and was able to find a different torrent containing the data I was looking for. =)

-Ares

[splintax]

At the very least, I believe the app should let you know what the problem is rather than displaying a generic error.

[nightshifted]

At the very least, I believe the app should let you know what the problem is rather than displaying a generic error.

That's what I was thinking as well, Splintax.

[chaosblade]

I believe the way to go, as said, is to allow such torrents to be used, but not created.

[dcorban]

Someone explain how one obscure client not loading particular torrent files is going to discourage anyone from doing anything? I understand the torrent maker not allowing such a small piece size, but the client should accept any valid torrent file.

[nightshifted]

1.2.3-beta-360 now accepts a .torrent with 16-KiB pieces, but its creation routines go down only to 32 KiB. That's consistent with other clients.